Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrog...Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrogen content for electrochemical reactions are rarely reported.In this work,transition metal carbonitride MXenes incorporated with Pt-based electrocatalysts,ranging from single atoms to sub-nanometer dimensions,are explored for hydrogen evolution reaction(HER).The fabricated Pt clusters/MXene catalyst exhibits superior HER performance compared to the single-atom-incorporated MXene and commercial Pt/C catalyst in both acidic and alkaline electrolytes.The optimized sample shows low overpotentials of 28,65,and 154 mV at a current densities of 10,100,and 500 m A cm^(-2),a small Tafel slope of 29 m V dec^(-1),a high mass activity of 1203 mA mgPt^(-1)and an excellent turnover frequency of 6.1 s^(-1)in the acidic electrolyte.Density functional theory calculations indicate that this high performance can be attributed to the enhanced active sites,increased surface functional groups,faster charge transfer dynamics,and stronger electronic interaction between Pt and MXene,resulting in optimized hydrogen absorption/desorption toward better HER.This work demonstrates that MXenes with a high content of nitrogen may be promising candidates for various catalytic reactions by incorporating single atoms or clusters.展开更多
Correction to:Nano-Micro Letters(2025)17:123 https://doi.org/10.1007/s40820-025-01654-y Following publication of the original article[1],the authors reported that Dr.Mohamed Bououdina’s affiliation needed to be corre...Correction to:Nano-Micro Letters(2025)17:123 https://doi.org/10.1007/s40820-025-01654-y Following publication of the original article[1],the authors reported that Dr.Mohamed Bououdina’s affiliation needed to be corrected from 1 to 2.The correct author affiliation has been provided in this Correction and the original article[1]has been corrected.展开更多
Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-5...Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-53),is successfully prepared via the hydrothermal method.In-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active species.More importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe(OH)_(2)after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@NiFeOOH.Furthermore,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center(εd),accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining steps.Consequently,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity(240 mV)with a small Tafel slope of 48.2 mV dec^(-1)and long-term durability(over1270 h at 10 m A cm^(-2)and 110 h at 200 mA cm^(-2)).This work presents a new perspective on designing highly efficient OER electrocatalysts.展开更多
Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent year...Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.展开更多
Ef fective and robust catalyst is the core of water splitting to produce hydrogen.Here, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performan...Ef fective and robust catalyst is the core of water splitting to produce hydrogen.Here, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performance for hydrogen evolution reaction(HER). With the VS concentration change from 2.4% to 8.5%, the H* adsorption strength on S sites changed and NiS_(2)-VS 5.9% shows the most optimized H* adsorption for HER with an ultralow onset potential(68 m V) and has long-term stability for 100 h in 1 M KOH media. In situ attenuated-total-reflection Fourier transform infrared spectroscopy(ATR-FTIRS) measurements are usually used to monitor the adsorption of intermediates. The S-H* peak of the Ni S_(2)-VS 5.9% appears at a very low voltage, which is favorable for the HER in alkaline media. Density functional theory calculations also demonstrate the Ni S_(2)-VS 5.9% has the optimal |ΔG^(H*)| of 0.17 e V. This work offers a simple and promising pathway to enhance catalytic activity via precise vacancies strategy.展开更多
Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based catalysts.By introducing a third metal int...Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based catalysts.By introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in AEMWEs.Herein,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this work.Experimental and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER performance.More critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.展开更多
The development of atomically dispersed platinum-based catalysts with high performance and welldefined active site structures is crucial for the commercialization of water electrolysis for hydrogen production.Herein,w...The development of atomically dispersed platinum-based catalysts with high performance and welldefined active site structures is crucial for the commercialization of water electrolysis for hydrogen production.Herein,we propose a coordination dual-shell synergistic regulation mechanism of coal pitchderived carbon-supported single atom Pt-N_(x)O_(y)-S_(1)catalytic sites by a self-assembly-pyrolysis strategy for promoting hydrogen evolution reaction(HER).The Pt-N_(3)O1-S_(1)sites exhibited the highest HER performance,with an overpotential of 92 mV at a current density of 400 mA cm^(-2).At 50 mV,the turnover frequency was 34.04 s^(-1)and the mass activity was 22.83 A mg_(Pt)^(-l),which is 63.4 times that of the 20%Pt/C catalyst.Theoretical calculations revealed that the coordination dual-shell impacts the electronic structure of the Pt atoms and the adsorption strength towards reactants synergistically.The S atoms in the second coordination shell weakened the strength of Pt-N first shell,resulting the more surface valence electrons around Pt atoms,exhibiting the most suitable adsorption free energy and enhancing the adsorption of H^(+)on Pt-N_(3)O_(1)-S_(1)sites,thus enhancing the electrocatalytic HER process by promoting Volmer step.This work reveals that coordination dual-shell synergistic regulation is an effective strategy for enhancing the electrocatalytic reaction process.展开更多
Optimizing the microdynamics in alkaline and neutral conditions is a significant but challenging task in developing pH-universal hydrogen evolution(HER)electrocatalysts.Herein,a unique Pt-O-Ni bridge has been construc...Optimizing the microdynamics in alkaline and neutral conditions is a significant but challenging task in developing pH-universal hydrogen evolution(HER)electrocatalysts.Herein,a unique Pt-O-Ni bridge has been constructed to alter the coordination and electronic environment between Pt nanoparticles(Pt_n)and nickel metaphosphate(NPO)substrate(Pt-NPO).Sufficient electron transfer from NPO to Pt_n to maintain an electron-rich environment and a low valence state of Pt_n.Furthermore,H*is produced from the H_(2)O dissociation on Ni site and then spillover toward Pt sites to bind into H_(2),which makes up for the insufficient H_(2)O dissociation ability of Pt in Volmer step.Pt-NPO exhibits long-term stability and only need the overpotentials of 22.3,33.0 and 30.5 mV to attain 10 mA cm^(-2)in alkaline,neutral and acidic media,respectively.The anion-exchange membrane(AEM)water electrolyzer catalyzed by Pt-NPO shows high water electrolysis performance that a cell voltage of 1.73 V is needed to obtain the current density of500 mA cm^(-2)in 1 M KOH at 80℃,at the same time maintains good stability for 350 h.The regulation strategy proposed in this work is helpful for the design and synthesis of highly efficient pH-universal HER electrocatalysts.展开更多
Dynamic adsorption processes of reaction intermediates for alkaline hydrogen evolution(HER)catalysts are still confusing to understand.Here,we report a series of A-site ordered quadruple perovskite ruthenium-based ele...Dynamic adsorption processes of reaction intermediates for alkaline hydrogen evolution(HER)catalysts are still confusing to understand.Here,we report a series of A-site ordered quadruple perovskite ruthenium-based electrocatalysts ACu_(3)Ru_(4)O_(12)(A=Na,Ca,Nd,and La),with the target sample SrCu_(3)Ru_(4)O_(12)exhibiting a very low overpotential(46 mV@10 mA·cm^(-2))and excellent catalytic stability with little decays after 48-h durability test.Precise tuning A-site cations can change the average valence state of Cu and Ru,thus the plot of HER activity versus the average Ru valence number shows a volcano-type relationship.Density functional theory indicates that the Ru 4d orbitals of SrCu3Ru4O12possesses the most suitable d-band center position among the five samples,which might be the key parameter to determine the catalytic performance.Our work provides further insight into the discovering advanced,efficient hydrogen evolution catalysts through designing precise descriptor.展开更多
Hydrogen evolution reaction(HER)has become a key factor affecting the cycling stability of aqueous Zn-ion batteries,while the corresponding fundamental issues involving HER are still unclear.Herein,the reaction mechan...Hydrogen evolution reaction(HER)has become a key factor affecting the cycling stability of aqueous Zn-ion batteries,while the corresponding fundamental issues involving HER are still unclear.Herein,the reaction mechanisms of HER on various crystalline surfaces have been investigated by first-principle calculations based on density functional theory.It is found that the Volmer step is the ratelimiting step of HER on the Zn(002)and(100)surfaces,while,the reaction rates of HER on the Zn(101),(102)and(103)surfaces are determined by the Tafel step.Moreover,the correlation between HER activity and the generalized coordination number(CN)of Zn at the surfaces has been revealed.The relatively weaker HER activity on Zn(002)surface can be attributed to the higher CN of surface Zn atom.The atomically uneven Zn(002)surface shows significantly higher HER activity than the flat Zn(002)surface as the CN of the surface Zn atom is lowered.The CN of surface Zn atom is proposed as a key descriptor of HER activity.Tuning the CN of surface Zn atom would be a vital strategy to inhibit HER on the Zn anode surface based on the presented theoretical studies.Furthermore,this work provides a theoretical basis for the in-depth understanding of HER on the Zn surface.展开更多
Hydrogen production by water reduction reactions has received considerable attention because hydrogen is considered a clean-energy carrier,key for a sustainable energy future.Computational methods have been widely use...Hydrogen production by water reduction reactions has received considerable attention because hydrogen is considered a clean-energy carrier,key for a sustainable energy future.Computational methods have been widely used to study the reaction mechanism of the hydrogen evolution reaction(HER),but the calculation results need to be supported by experimental results and direct evidence to confirm the mechanistic insights.In this review,we discuss the fundamental principles of the in situ spectroscopic strategy and a theoretical model for a mechanistic understanding of the HER.In addition,we investigate recent studies by in situ Fourier transform infrared(FTIR),Raman spectroscopy,and X-ray absorption spectroscopy(XAS) and cover new findings that occur at the catalyst-electrolyte interface during HER.These spectroscopic strategies provide practical ways to elucidate catalyst phase,reaction intermediate,catalyst-electrolyte interface,intermediate binding energy,metal valency state,and coordination environment during HER.展开更多
Photoelectrochemical hydrogen evolution reaction(HER)is taken into account as an alternative to effective hydrogen production,emphasizing the importance of catalysts.The magnetism of catalysts could modulate the adsor...Photoelectrochemical hydrogen evolution reaction(HER)is taken into account as an alternative to effective hydrogen production,emphasizing the importance of catalysts.The magnetism of catalysts could modulate the adsorption of the H atom and further enhance the HER activity.Herein,doping the double transition metal atoms on SnS_(2) nanosheet(TM_(2)@SnS_(2))to form the efficient magnetic catalyst is proposed to explore the spin magnetic effect on the HER performance.By performing first-principles calculations,nonmagnetic V_(2)@SnS_(2) is proved to be the candidate of the HER catalyst;nevertheless,the HER activities of antiferromagnetic and ferromagnetic V_(2)@SnS_(2) are relatively inferior due to the spin-induced charge redistribution.Meanwhile,machine learning analysis shows the absolute importance of the electronic structure of TM dopants and surrounding S ligands,and the HER activity could be predicted by the modified band centers of S-3p_(z) and TM-d.Furthermore,the proof-of-concept experiment has substantiated the above theoretical predictions by significantly increasing liner sweep voltammetry and photocurrent with applied magnetic field.This work provides a new avenue for uncovering the spin catalytic mechanism and the exploration and design of efficient HER catalysts.展开更多
Interfacial water molecules are the most important participants in the hydrogen evolution reaction(HER).Hence,understanding the behavior and role that interfacial water plays will ultimately reveal the HER mechanism.U...Interfacial water molecules are the most important participants in the hydrogen evolution reaction(HER).Hence,understanding the behavior and role that interfacial water plays will ultimately reveal the HER mechanism.Unfortunately,investigating interfacial water is extremely challenging owing to the interference caused by bulk water molecules and complexity of the interfacial environment.Here,the behaviors of interfacial water in different cationic electrolytes on Pd surfaces were investigated by the electrochemistry,in situ core-shell nanostructure enhanced Raman spectroscopy and theoretical simulation techniques.Direct spectral evidence reveals a red shift in the frequency and a decrease in the intensity of interfacial water as the potential is shifted in the positively direction.When comparing the different cation electrolyte systems at a given potential,the frequency of the interfacial water peak increases in the specified order:Li+<Na^(+)<K^(+)<Ca^(2+)<Sr^(2+).The structure of interfacial water was optimized by adjusting the radius,valence,and concentration of cation to form the two-H down structure.This unique interfacial water structure will improve the charge transfer efficiency between the water and electrode further enhancing the HER performance.Therefore,local cation tuning strategies can be used to improve the HER performance by optimizing the interfacial water structure.展开更多
The parasitic hydrogen evolution reaction(HER)in the negative half-cell of vanadium redox flow batteries(VRFBs)causes severe efficiency losses.Thus,a deeper understanding of this process and the accompanying bubble fo...The parasitic hydrogen evolution reaction(HER)in the negative half-cell of vanadium redox flow batteries(VRFBs)causes severe efficiency losses.Thus,a deeper understanding of this process and the accompanying bubble formation is crucial.This benchmarking study locally analyzes the bubble distribution in thick,porous electrodes for the first time using deep learning-based image segmentation of synchrotron X-ray micro-tomograms.Each large three-dimensional data set was processed precisely in less than one minute while minimizing human errors and pointing out areas of increased HER activity in VRFBs.The study systematically varies the electrode potential and material,concluding that more negative electrode potentials of-200 m V vs.reversible hydrogen electrode(RHE)and lower cause more substantial bubble formation,resulting in bubble fractions of around 15%–20%in carbon felt electrodes.Contrarily,the bubble fractions stay only around 2%in an electrode combining carbon felt and carbon paper.The detected areas with high HER activity,such as the border subregion with more than 30%bubble fraction in carbon felt electrodes,the cutting edges,and preferential spots in the electrode bulk,are potential-independent and suggest that larger electrodes with a higher bulk-to-border ratio might reduce HER-related performance losses.The described combination of electrochemical measurements,local X-ray microtomography,AI-based segmentation,and 3D morphometric analysis is a powerful and novel approach for local bubble analysis in three-dimensional porous electrodes,providing an essential toolkit for a broad community working on bubble-generating electrochemical systems.展开更多
The slow water dissociation is the rate-determining step that slows down the reaction rate in alkaline hydrogen evolution reaction(HER).Optimizing the surface electronic structure of the catalyst to lower the energy b...The slow water dissociation is the rate-determining step that slows down the reaction rate in alkaline hydrogen evolution reaction(HER).Optimizing the surface electronic structure of the catalyst to lower the energy barrier of water dissociation and regulating the binding strength of adsorption intermediates are crucial strategy for boosting the catalytic performance of HER.In this study,RuO_(2)/BaRuO_(3)(RBRO)heterostructures with abundant oxygen vacancies and lattice distortion were in-situ constructed under a low temperature via the thermal decomposition of gel-precursor.The RBRO heterostructures obtained at 550℃ exhibited the highest HER activity in 1 M KOH,showing an ultra-low overpotential of 16 mV at 10 mA cm^(-2)and a Tafel slope of 33.37 m V dec^(-1).Additionally,the material demonstrated remarkable durability,with only 25 mV of degradation in overpotential after 200 h of stability testing at 10 mA cm^(-2).Density functional theory calculations revealed that the redistribution of charges at the heterojunction interface can optimize the binding energies of H*and OH*and effectively lower the energy barrier of water dissociation.This research offers novel perspectives on surpassing the water dissociation threshold of alkaline HER catalysts by means of a systematic design of heterogeneous interfaces.展开更多
Designing highly efficient Pt-free electrocatalysts with low overpotential for an alkaline hydrogen evolution reaction(HER)remains a significant challenge.Here,a novel and efficient cobalt(Co),ruthenium(Ru)bimetallic ...Designing highly efficient Pt-free electrocatalysts with low overpotential for an alkaline hydrogen evolution reaction(HER)remains a significant challenge.Here,a novel and efficient cobalt(Co),ruthenium(Ru)bimetallic electrocatalyst composed of CoRu nanoalloy decorated on the N-doped carbon nanotubes(CoRu@N-CNTs),was prepared by reacting fullerenol with melamine via hydrothermal treatment and followed by pyrolysis.Benefiting from the electronic communication between Co and Ru sites,the as-obtained CoRu@N-CNTs catalyst exhibited superior electrocatalytic HER activity.To deliver a current density of 10 mA·cm^(-2),it required an overpotential of merely 19 mV along with a Tafel slope of 26.19 mV·dec^(-1)in 1 mol·L^(-1)potassium hydroxide(KOH)solution,outperforming the benchmark Pt/C catalyst.The present work would pave a new way towards the design and construction of an efficient electrocatalyst for energy storage and conversion.展开更多
Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a b...Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a binary nanophotocatalyst fabricated by blending two polymers,PS-PEG5(PS)and PBT-PEG5(PBT),with matched absorption and emission spectra,enabling a Forster resonance energy transfer(FRET)process for enhanced photocatalysis.These heterostructure nanophotocatalysts are processed using a facile and scalable flash nanoprecipitation(FNP)technique with precious kinetic control over binary nanoparticle formation.The resulting nanoparticles exhibit an exceptional photocatalytic hydrogen evolution rate up to 65 mmol g^(-1) h^(-1),2.5 times higher than that single component nanoparticles.Characterizations through fluorescence spectra and transient absorption spectra confirm the hetero-energy transfer within the binary nanoparticles,which prolongs the excited-state lifetime and extends the namely“effective exciton diffusion length”.Our finding opens new avenues for designing efficient organic photocatalysts by improving exciton migration.展开更多
In-situ conversion of subsurface hydrocarbons via electromagnetic(EM)heating has emerged as a promising technology for producing carbon-zero and affordable hydrogen(H_(2))directly from natural gas reservoirs.However,t...In-situ conversion of subsurface hydrocarbons via electromagnetic(EM)heating has emerged as a promising technology for producing carbon-zero and affordable hydrogen(H_(2))directly from natural gas reservoirs.However,the reaction pathways and role of water as an additional hydrogen donor in EM-assisted methane-to-hydrogen(CH_(4)-to-H_(2))conversion are poorly understood.Herein,we employ a combination of lab-scale EM-heating experiments and reaction modeling analyses to unravel reaction pathways and elucidate water's role in enhancing hydrogen production.The labelled hydrogen isotope of deuterium oxide(D_(2)O)is used to trace the sources of hydrogen.The results show that water significantly boosts hydrogen yield via coke gasification at around 400℃and steam methane reforming(SMR)reaction at over 600℃in the presence of sandstone.Water-gas shift reaction exhibits a minor impact on this enhancement.Reaction mechanism analyses reveal that the involvement of water can initiate auto-catalytic loop reactions with methane,which not only generates extra hydrogen but also produces OH radicals that enhance the reactants'reactivity.This work provides crucial insights into the reaction mechanisms involved in water-carbon-methane interactions and underscores water's potential as a hydrogen donor for in-situ hydrogen production from natural gas reservoirs.It also addresses the challenges related to carbon deposition and in-situ catalyst regeneration during EM heating,thus derisking this technology and laying a foundation for future pilots.展开更多
This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production fr...This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.展开更多
Although the water splitting-based generation of hydrogen as an energy carrier can help to mitigate the global problems of energy shortage and climate change,the practical implementation of this strategy is hindered b...Although the water splitting-based generation of hydrogen as an energy carrier can help to mitigate the global problems of energy shortage and climate change,the practical implementation of this strategy is hindered by the absence of inexpensive high-performance electrocatalysts for the hydrogen evolution reaction (HER).Re-based HER electrocatalysts exhibit predictable high performance within the entire pH range but suffer from arduous formation (i.e.,vulnerability to oxidation) and uncontrollable aggregation,which strongly discourages the maximisation of active site exposure required for activity enhancement.To overcome these limitations,we herein hydrothermally synthesise Re nanoclusters uniformly distributed on nanosheet supports,such as reduced graphene oxide nanosheets (Re NCs@rGO),revealing that this hybrid features abundant exposed active sites and high oxidation resistance.The obtained electrocatalysts were elaborately characterized by microscopic and spectroscopic analyses.Also,density functional theory calculations confirm the optimised synthesis of Re NCs@rGO and indicate the crucial role of Re–O–C junction formation in securing durability.The effective suppression of Re nanocluster detachment/dissolution under HER conditions endows Re NCs@rGO with high electron conductivity and electrochemical stability,resulting in a durability superior to that of commercial Pt/C and an activity similar to that of this reference.As a result,Re NCs@rGO exhibited remarkably small HER overpotentials of 110,130,and 93 m V to deliver a current density of 10 mA cm^(-2) in 0.5 M H_(2)SO_(4),1 M PBS,and 1 M KOH,respectively.Thus,Re NCs@rGO is a promising alternative to conventional Pt-group-metal catalysts and should find applications in next-generation high-performance water splitting systems.展开更多
基金the final support of ARC DP220103045the startup support of KFUPMPrince Sultan University for their support。
文摘Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrogen content for electrochemical reactions are rarely reported.In this work,transition metal carbonitride MXenes incorporated with Pt-based electrocatalysts,ranging from single atoms to sub-nanometer dimensions,are explored for hydrogen evolution reaction(HER).The fabricated Pt clusters/MXene catalyst exhibits superior HER performance compared to the single-atom-incorporated MXene and commercial Pt/C catalyst in both acidic and alkaline electrolytes.The optimized sample shows low overpotentials of 28,65,and 154 mV at a current densities of 10,100,and 500 m A cm^(-2),a small Tafel slope of 29 m V dec^(-1),a high mass activity of 1203 mA mgPt^(-1)and an excellent turnover frequency of 6.1 s^(-1)in the acidic electrolyte.Density functional theory calculations indicate that this high performance can be attributed to the enhanced active sites,increased surface functional groups,faster charge transfer dynamics,and stronger electronic interaction between Pt and MXene,resulting in optimized hydrogen absorption/desorption toward better HER.This work demonstrates that MXenes with a high content of nitrogen may be promising candidates for various catalytic reactions by incorporating single atoms or clusters.
文摘Correction to:Nano-Micro Letters(2025)17:123 https://doi.org/10.1007/s40820-025-01654-y Following publication of the original article[1],the authors reported that Dr.Mohamed Bououdina’s affiliation needed to be corrected from 1 to 2.The correct author affiliation has been provided in this Correction and the original article[1]has been corrected.
基金Natural Science Foundation of China(Grant No.NSFC-22072062,22202098)。
文摘Designing highly active and stable electrocatalysts of oxygen evolution reaction(OER)is one of the crucial challenges.In this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium(Rh@NiFe-MIL-53),is successfully prepared via the hydrothermal method.In-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active species.More importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe(OH)_(2)after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@NiFeOOH.Furthermore,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center(εd),accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining steps.Consequently,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity(240 mV)with a small Tafel slope of 48.2 mV dec^(-1)and long-term durability(over1270 h at 10 m A cm^(-2)and 110 h at 200 mA cm^(-2)).This work presents a new perspective on designing highly efficient OER electrocatalysts.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51902101 and 21875203)the Natural Science Foundation of Hunan Province(Nos.2021JJ40044 and 2023JJ50287)Natural Science Foundation of Jiangsu Province(No.BK20201381).
文摘Deformable catalytic material with excellent flexible structure is a new type of catalyst that has been applied in various chemical reactions,especially electrocatalytic hydrogen evolution reaction(HER).In recent years,deformable catalysts for HER have made great progress and would become a research hotspot.The catalytic activities of deformable catalysts could be adjustable by the strain engineering and surface reconfiguration.The surface curvature of flexible catalytic materials is closely related to the electrocatalytic HER properties.Here,firstly,we systematically summarized self-adaptive catalytic performance of deformable catalysts and various micro–nanostructures evolution in catalytic HER process.Secondly,a series of strategies to design highly active catalysts based on the mechanical flexibility of lowdimensional nanomaterials were summarized.Last but not least,we presented the challenges and prospects of the study of flexible and deformable micro–nanostructures of electrocatalysts,which would further deepen the understanding of catalytic mechanisms of deformable HER catalyst.
基金funded by the National Natural Science Foundation of China (NSFC) (Nos. 22221001, 22201115, 21931001, and 21922105)the Special Fund Project of Guiding Scientific and Technological Innovation Development of Gansu Province (2019ZX–04)+3 种基金the 111 Project (B20027)by the Fundamental Research Funds for the Central Universities (lzujbky-2023-eyt03)support Natural Science Foundation of Gansu Providence (22JR5RA540)Gansu Province Youth Science and Technology Talent Promotion Project (GXH202220530-02)。
文摘Ef fective and robust catalyst is the core of water splitting to produce hydrogen.Here, we report an anionic etching method to tailor the sulfur vacancy(VS) of NiS_(2) to further enhance the electrocatalytic performance for hydrogen evolution reaction(HER). With the VS concentration change from 2.4% to 8.5%, the H* adsorption strength on S sites changed and NiS_(2)-VS 5.9% shows the most optimized H* adsorption for HER with an ultralow onset potential(68 m V) and has long-term stability for 100 h in 1 M KOH media. In situ attenuated-total-reflection Fourier transform infrared spectroscopy(ATR-FTIRS) measurements are usually used to monitor the adsorption of intermediates. The S-H* peak of the Ni S_(2)-VS 5.9% appears at a very low voltage, which is favorable for the HER in alkaline media. Density functional theory calculations also demonstrate the Ni S_(2)-VS 5.9% has the optimal |ΔG^(H*)| of 0.17 e V. This work offers a simple and promising pathway to enhance catalytic activity via precise vacancies strategy.
基金financially supported by the National Natural Science Foundation of China(22309137,22279095)Open subject project State Key Laboratory of New Textile Materials and Advanced Processing Technologies(FZ2023001).
文摘Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based catalysts.By introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in AEMWEs.Herein,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this work.Experimental and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER performance.More critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.
基金supported by the National Natural Science Foundation of China(22108306,22478432 and 22406191)Taishan Scholars Program of Shandong Province(tsqn201909065)the Natural Science Foundation of Shandong Province(ZR2024JQ004,ZR2021YQ15)。
文摘The development of atomically dispersed platinum-based catalysts with high performance and welldefined active site structures is crucial for the commercialization of water electrolysis for hydrogen production.Herein,we propose a coordination dual-shell synergistic regulation mechanism of coal pitchderived carbon-supported single atom Pt-N_(x)O_(y)-S_(1)catalytic sites by a self-assembly-pyrolysis strategy for promoting hydrogen evolution reaction(HER).The Pt-N_(3)O1-S_(1)sites exhibited the highest HER performance,with an overpotential of 92 mV at a current density of 400 mA cm^(-2).At 50 mV,the turnover frequency was 34.04 s^(-1)and the mass activity was 22.83 A mg_(Pt)^(-l),which is 63.4 times that of the 20%Pt/C catalyst.Theoretical calculations revealed that the coordination dual-shell impacts the electronic structure of the Pt atoms and the adsorption strength towards reactants synergistically.The S atoms in the second coordination shell weakened the strength of Pt-N first shell,resulting the more surface valence electrons around Pt atoms,exhibiting the most suitable adsorption free energy and enhancing the adsorption of H^(+)on Pt-N_(3)O_(1)-S_(1)sites,thus enhancing the electrocatalytic HER process by promoting Volmer step.This work reveals that coordination dual-shell synergistic regulation is an effective strategy for enhancing the electrocatalytic reaction process.
基金supported by the National Natural Science Foundation of China(22202080,22034006 and 22393930)Jilin Talent Development Foundation(E41S2001)the National Key Research and Development Program of China(2022YFF0710000).
文摘Optimizing the microdynamics in alkaline and neutral conditions is a significant but challenging task in developing pH-universal hydrogen evolution(HER)electrocatalysts.Herein,a unique Pt-O-Ni bridge has been constructed to alter the coordination and electronic environment between Pt nanoparticles(Pt_n)and nickel metaphosphate(NPO)substrate(Pt-NPO).Sufficient electron transfer from NPO to Pt_n to maintain an electron-rich environment and a low valence state of Pt_n.Furthermore,H*is produced from the H_(2)O dissociation on Ni site and then spillover toward Pt sites to bind into H_(2),which makes up for the insufficient H_(2)O dissociation ability of Pt in Volmer step.Pt-NPO exhibits long-term stability and only need the overpotentials of 22.3,33.0 and 30.5 mV to attain 10 mA cm^(-2)in alkaline,neutral and acidic media,respectively.The anion-exchange membrane(AEM)water electrolyzer catalyzed by Pt-NPO shows high water electrolysis performance that a cell voltage of 1.73 V is needed to obtain the current density of500 mA cm^(-2)in 1 M KOH at 80℃,at the same time maintains good stability for 350 h.The regulation strategy proposed in this work is helpful for the design and synthesis of highly efficient pH-universal HER electrocatalysts.
基金Project supported financially by the National Key Research and Development Program of China(Grant No.2023YFA1406000)the National Natural Science Foundation of China(Grant Nos.22171283 and 12474002)+3 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.2023ZCJH03 and 2021XD-A041)the Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications,China)the Teaching Reform Projects at BUPT(Grant No.2022CXCYB03)the BUPT Excellent Ph.D.Students Foundation(Grant No.CX2023108)。
文摘Dynamic adsorption processes of reaction intermediates for alkaline hydrogen evolution(HER)catalysts are still confusing to understand.Here,we report a series of A-site ordered quadruple perovskite ruthenium-based electrocatalysts ACu_(3)Ru_(4)O_(12)(A=Na,Ca,Nd,and La),with the target sample SrCu_(3)Ru_(4)O_(12)exhibiting a very low overpotential(46 mV@10 mA·cm^(-2))and excellent catalytic stability with little decays after 48-h durability test.Precise tuning A-site cations can change the average valence state of Cu and Ru,thus the plot of HER activity versus the average Ru valence number shows a volcano-type relationship.Density functional theory indicates that the Ru 4d orbitals of SrCu3Ru4O12possesses the most suitable d-band center position among the five samples,which might be the key parameter to determine the catalytic performance.Our work provides further insight into the discovering advanced,efficient hydrogen evolution catalysts through designing precise descriptor.
基金This work was financially supported by the National Natural Science Foundation of China(22075171)Natural Science Foundation of Shanghai(23ZR1423400)The firstprinciples calculations were supported by the High Performance Computing Center of Shanghai University.
文摘Hydrogen evolution reaction(HER)has become a key factor affecting the cycling stability of aqueous Zn-ion batteries,while the corresponding fundamental issues involving HER are still unclear.Herein,the reaction mechanisms of HER on various crystalline surfaces have been investigated by first-principle calculations based on density functional theory.It is found that the Volmer step is the ratelimiting step of HER on the Zn(002)and(100)surfaces,while,the reaction rates of HER on the Zn(101),(102)and(103)surfaces are determined by the Tafel step.Moreover,the correlation between HER activity and the generalized coordination number(CN)of Zn at the surfaces has been revealed.The relatively weaker HER activity on Zn(002)surface can be attributed to the higher CN of surface Zn atom.The atomically uneven Zn(002)surface shows significantly higher HER activity than the flat Zn(002)surface as the CN of the surface Zn atom is lowered.The CN of surface Zn atom is proposed as a key descriptor of HER activity.Tuning the CN of surface Zn atom would be a vital strategy to inhibit HER on the Zn anode surface based on the presented theoretical studies.Furthermore,this work provides a theoretical basis for the in-depth understanding of HER on the Zn surface.
基金the immense support provided by the National Research Foundation of Korea(NRF)Grant funded by the Korean Government(MSIT)(RS-2023–00210114)the National R&D Program through the National Research Foundation of Korea(NRF)funded by Ministry of Science and ICT(2021M3D1A2051636)。
文摘Hydrogen production by water reduction reactions has received considerable attention because hydrogen is considered a clean-energy carrier,key for a sustainable energy future.Computational methods have been widely used to study the reaction mechanism of the hydrogen evolution reaction(HER),but the calculation results need to be supported by experimental results and direct evidence to confirm the mechanistic insights.In this review,we discuss the fundamental principles of the in situ spectroscopic strategy and a theoretical model for a mechanistic understanding of the HER.In addition,we investigate recent studies by in situ Fourier transform infrared(FTIR),Raman spectroscopy,and X-ray absorption spectroscopy(XAS) and cover new findings that occur at the catalyst-electrolyte interface during HER.These spectroscopic strategies provide practical ways to elucidate catalyst phase,reaction intermediate,catalyst-electrolyte interface,intermediate binding energy,metal valency state,and coordination environment during HER.
基金supported by the National Natural Science Foundation of China(51972227)。
文摘Photoelectrochemical hydrogen evolution reaction(HER)is taken into account as an alternative to effective hydrogen production,emphasizing the importance of catalysts.The magnetism of catalysts could modulate the adsorption of the H atom and further enhance the HER activity.Herein,doping the double transition metal atoms on SnS_(2) nanosheet(TM_(2)@SnS_(2))to form the efficient magnetic catalyst is proposed to explore the spin magnetic effect on the HER performance.By performing first-principles calculations,nonmagnetic V_(2)@SnS_(2) is proved to be the candidate of the HER catalyst;nevertheless,the HER activities of antiferromagnetic and ferromagnetic V_(2)@SnS_(2) are relatively inferior due to the spin-induced charge redistribution.Meanwhile,machine learning analysis shows the absolute importance of the electronic structure of TM dopants and surrounding S ligands,and the HER activity could be predicted by the modified band centers of S-3p_(z) and TM-d.Furthermore,the proof-of-concept experiment has substantiated the above theoretical predictions by significantly increasing liner sweep voltammetry and photocurrent with applied magnetic field.This work provides a new avenue for uncovering the spin catalytic mechanism and the exploration and design of efficient HER catalysts.
基金the National Key Research and Development Program of China(2019YFA0705400)the National Natural Science Foundation of China(T2293692,21925404,22021001,21991151,and 22002036)+1 种基金the Natural Science Foundation of Fujian Province of China(2021J06001)the National Natural Science Foundation of Henan province(232300421081).
文摘Interfacial water molecules are the most important participants in the hydrogen evolution reaction(HER).Hence,understanding the behavior and role that interfacial water plays will ultimately reveal the HER mechanism.Unfortunately,investigating interfacial water is extremely challenging owing to the interference caused by bulk water molecules and complexity of the interfacial environment.Here,the behaviors of interfacial water in different cationic electrolytes on Pd surfaces were investigated by the electrochemistry,in situ core-shell nanostructure enhanced Raman spectroscopy and theoretical simulation techniques.Direct spectral evidence reveals a red shift in the frequency and a decrease in the intensity of interfacial water as the potential is shifted in the positively direction.When comparing the different cation electrolyte systems at a given potential,the frequency of the interfacial water peak increases in the specified order:Li+<Na^(+)<K^(+)<Ca^(2+)<Sr^(2+).The structure of interfacial water was optimized by adjusting the radius,valence,and concentration of cation to form the two-H down structure.This unique interfacial water structure will improve the charge transfer efficiency between the water and electrode further enhancing the HER performance.Therefore,local cation tuning strategies can be used to improve the HER performance by optimizing the interfacial water structure.
基金financial support through a KekuléPh.D.fellowship by the Fonds der Chemischen Industrie(FCI)support from the China Scholarship Council(No.202106950013)。
文摘The parasitic hydrogen evolution reaction(HER)in the negative half-cell of vanadium redox flow batteries(VRFBs)causes severe efficiency losses.Thus,a deeper understanding of this process and the accompanying bubble formation is crucial.This benchmarking study locally analyzes the bubble distribution in thick,porous electrodes for the first time using deep learning-based image segmentation of synchrotron X-ray micro-tomograms.Each large three-dimensional data set was processed precisely in less than one minute while minimizing human errors and pointing out areas of increased HER activity in VRFBs.The study systematically varies the electrode potential and material,concluding that more negative electrode potentials of-200 m V vs.reversible hydrogen electrode(RHE)and lower cause more substantial bubble formation,resulting in bubble fractions of around 15%–20%in carbon felt electrodes.Contrarily,the bubble fractions stay only around 2%in an electrode combining carbon felt and carbon paper.The detected areas with high HER activity,such as the border subregion with more than 30%bubble fraction in carbon felt electrodes,the cutting edges,and preferential spots in the electrode bulk,are potential-independent and suggest that larger electrodes with a higher bulk-to-border ratio might reduce HER-related performance losses.The described combination of electrochemical measurements,local X-ray microtomography,AI-based segmentation,and 3D morphometric analysis is a powerful and novel approach for local bubble analysis in three-dimensional porous electrodes,providing an essential toolkit for a broad community working on bubble-generating electrochemical systems.
基金supported by the National Natural Science Foundation of China (21721003,22202080 and 22034006)。
文摘The slow water dissociation is the rate-determining step that slows down the reaction rate in alkaline hydrogen evolution reaction(HER).Optimizing the surface electronic structure of the catalyst to lower the energy barrier of water dissociation and regulating the binding strength of adsorption intermediates are crucial strategy for boosting the catalytic performance of HER.In this study,RuO_(2)/BaRuO_(3)(RBRO)heterostructures with abundant oxygen vacancies and lattice distortion were in-situ constructed under a low temperature via the thermal decomposition of gel-precursor.The RBRO heterostructures obtained at 550℃ exhibited the highest HER activity in 1 M KOH,showing an ultra-low overpotential of 16 mV at 10 mA cm^(-2)and a Tafel slope of 33.37 m V dec^(-1).Additionally,the material demonstrated remarkable durability,with only 25 mV of degradation in overpotential after 200 h of stability testing at 10 mA cm^(-2).Density functional theory calculations revealed that the redistribution of charges at the heterojunction interface can optimize the binding energies of H*and OH*and effectively lower the energy barrier of water dissociation.This research offers novel perspectives on surpassing the water dissociation threshold of alkaline HER catalysts by means of a systematic design of heterogeneous interfaces.
基金supported by the National Natural Science Foundation of China(No.52072226,U22A20144)Key Research and Development Program of Shaanxi(2024GX-YBXM-466)+1 种基金Science and Technology Program of Xi'an,China(22GXFW0013)Science and Technology Program of Weiyang District of Xi'an,China(202315)。
文摘Designing highly efficient Pt-free electrocatalysts with low overpotential for an alkaline hydrogen evolution reaction(HER)remains a significant challenge.Here,a novel and efficient cobalt(Co),ruthenium(Ru)bimetallic electrocatalyst composed of CoRu nanoalloy decorated on the N-doped carbon nanotubes(CoRu@N-CNTs),was prepared by reacting fullerenol with melamine via hydrothermal treatment and followed by pyrolysis.Benefiting from the electronic communication between Co and Ru sites,the as-obtained CoRu@N-CNTs catalyst exhibited superior electrocatalytic HER activity.To deliver a current density of 10 mA·cm^(-2),it required an overpotential of merely 19 mV along with a Tafel slope of 26.19 mV·dec^(-1)in 1 mol·L^(-1)potassium hydroxide(KOH)solution,outperforming the benchmark Pt/C catalyst.The present work would pave a new way towards the design and construction of an efficient electrocatalyst for energy storage and conversion.
基金supported by National Natural Science Foundation of China(NSFC,22338006,92356301,9235630033 and 22375062)Shanghai Municipal Science and Technology Major Project(21JC1401700)+4 种基金Shanghai Pilot Program for Basic Research(22TQ1400100-10)Fundamental Research Funds for the Central UniversitiesShanghai Pujiang Program(22PJ1402400)“Chenguang Program”supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(22CGA32)the Young Elite Scientists Sponsorship Program by CAST(2023QNRC001).
文摘Organic nanophotocatalysts are promising candidates for solar fuels production,but they still face the challenge of unfavorable geminate recombination due to the limited exciton diffusion lengths.Here,we introduce a binary nanophotocatalyst fabricated by blending two polymers,PS-PEG5(PS)and PBT-PEG5(PBT),with matched absorption and emission spectra,enabling a Forster resonance energy transfer(FRET)process for enhanced photocatalysis.These heterostructure nanophotocatalysts are processed using a facile and scalable flash nanoprecipitation(FNP)technique with precious kinetic control over binary nanoparticle formation.The resulting nanoparticles exhibit an exceptional photocatalytic hydrogen evolution rate up to 65 mmol g^(-1) h^(-1),2.5 times higher than that single component nanoparticles.Characterizations through fluorescence spectra and transient absorption spectra confirm the hetero-energy transfer within the binary nanoparticles,which prolongs the excited-state lifetime and extends the namely“effective exciton diffusion length”.Our finding opens new avenues for designing efficient organic photocatalysts by improving exciton migration.
基金supported by a generous gift from The CH Foundationthe support from the Distinguished Graduate Student Assistantship and the Graduate Research Support Award at Texas Tech University+1 种基金the Aid fund from AAPGthe Matejek Family Faculty Fellowship。
文摘In-situ conversion of subsurface hydrocarbons via electromagnetic(EM)heating has emerged as a promising technology for producing carbon-zero and affordable hydrogen(H_(2))directly from natural gas reservoirs.However,the reaction pathways and role of water as an additional hydrogen donor in EM-assisted methane-to-hydrogen(CH_(4)-to-H_(2))conversion are poorly understood.Herein,we employ a combination of lab-scale EM-heating experiments and reaction modeling analyses to unravel reaction pathways and elucidate water's role in enhancing hydrogen production.The labelled hydrogen isotope of deuterium oxide(D_(2)O)is used to trace the sources of hydrogen.The results show that water significantly boosts hydrogen yield via coke gasification at around 400℃and steam methane reforming(SMR)reaction at over 600℃in the presence of sandstone.Water-gas shift reaction exhibits a minor impact on this enhancement.Reaction mechanism analyses reveal that the involvement of water can initiate auto-catalytic loop reactions with methane,which not only generates extra hydrogen but also produces OH radicals that enhance the reactants'reactivity.This work provides crucial insights into the reaction mechanisms involved in water-carbon-methane interactions and underscores water's potential as a hydrogen donor for in-situ hydrogen production from natural gas reservoirs.It also addresses the challenges related to carbon deposition and in-situ catalyst regeneration during EM heating,thus derisking this technology and laying a foundation for future pilots.
基金funding from the"Ministero dell'Universitàe della Ricerca(MUR)"(Italy)under the"Dipartimento di Eccellenza 2018-2022"program.
文摘This work aimed to study the efficiency of the reverse micelle(RM)preparation route in the syntheses of sub-5 nm Fe-doped CeO_(2)nanocrystals for boosting the visible-light-driven photocatalytic hydrogen production from methanol aqueous solutions.The effectiveness of confining precipitation reactions within micellar cages was evaluated through extensive physicochemical cha racterization.In particula r,the nominal composition(0-5 mol%Fe)was preserved as ascertained by ICP-MS analysis,and the absence of separate iron-containing crystalline phases was supported by X-ray diffraction.The effective aliovalent doping and modulation of the optical properties were investigated using UV-Vis,Raman,and photoluminescence spectroscopies.2.5 mol%iron was found to be an optimal content to achieve a significant decrease in the band gap,enhance the concentration of oxygen vacancy defects,and increase the charge carrier lifetime.The photocatalytic activity of Fe-doped CeO_(2)prepared at different Fe contents with RM preparation was studied and compared with undoped CeO_(2).The optimal iron load was identified to be2.5 mol%,achieving the highest hydrogen production(7566μmol L-1after 240 min under visible light).Moreover,for comparison,the conventional precipitation(P)method was adopted to prepare iron containing CeO_(2)at the optimal content(2.5 mol%Fe).The Fe-doped CeO_(2)catalyst prepared by RM showed a significantly higher hydrogen production than that obtained with the sample prepared by the P method.The optimal Fe-doped CeO_(2),prepared by the RM method,was stable for six reuse cycles.Moreover,the role of water in the mechanism of photocatalytic hydrogen evolution under visible light was studied through the test in the presence of D2O.The obtained results evidenced that hydrogen was produced from the reduction of H^(+)by the electrons promoted in the conduction band,while methanol was preferentially oxidized by the photogenerated positive holes.
基金supported by research grants of the NRF (2019K1A3A1A21032033 and 2021R1A4A1024129) funded by the National Research Foundation under the Ministry of Science, ICT & Future, Koreasupported by the Korea Institute for Advancement of Technology (KIAT) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (P0017363)。
文摘Although the water splitting-based generation of hydrogen as an energy carrier can help to mitigate the global problems of energy shortage and climate change,the practical implementation of this strategy is hindered by the absence of inexpensive high-performance electrocatalysts for the hydrogen evolution reaction (HER).Re-based HER electrocatalysts exhibit predictable high performance within the entire pH range but suffer from arduous formation (i.e.,vulnerability to oxidation) and uncontrollable aggregation,which strongly discourages the maximisation of active site exposure required for activity enhancement.To overcome these limitations,we herein hydrothermally synthesise Re nanoclusters uniformly distributed on nanosheet supports,such as reduced graphene oxide nanosheets (Re NCs@rGO),revealing that this hybrid features abundant exposed active sites and high oxidation resistance.The obtained electrocatalysts were elaborately characterized by microscopic and spectroscopic analyses.Also,density functional theory calculations confirm the optimised synthesis of Re NCs@rGO and indicate the crucial role of Re–O–C junction formation in securing durability.The effective suppression of Re nanocluster detachment/dissolution under HER conditions endows Re NCs@rGO with high electron conductivity and electrochemical stability,resulting in a durability superior to that of commercial Pt/C and an activity similar to that of this reference.As a result,Re NCs@rGO exhibited remarkably small HER overpotentials of 110,130,and 93 m V to deliver a current density of 10 mA cm^(-2) in 0.5 M H_(2)SO_(4),1 M PBS,and 1 M KOH,respectively.Thus,Re NCs@rGO is a promising alternative to conventional Pt-group-metal catalysts and should find applications in next-generation high-performance water splitting systems.
