The development of highly active,stable and inexpensive electrocatalysts for hydrogen production by defects and morphology engineering remains a great challenge.Herein,S vacancies-rich Ni_(3)S_(2)@Cu_(2)S nan-otube he...The development of highly active,stable and inexpensive electrocatalysts for hydrogen production by defects and morphology engineering remains a great challenge.Herein,S vacancies-rich Ni_(3)S_(2)@Cu_(2)S nan-otube heterojunction arrays were in-situ grown on copper foam(V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF)for efficient electrocatalytic overall water splitting.With the merits of nanotube arrays and efficient electronic mod-ulation drived by the OD vacancy defect and 2D heterojunction defect,the resultant V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF electrocatalyst exhibits excellent electrocatalytic activity with a low overpotential of 47 mV for the hydrogen evolution reaction(HER)at 10 mA cm^(-2) current density,and 263 mV for the oxygen evolution reaction(OER)at 50 mA cm^(-2) current density,as well as a cell voltage of 1.48 V at 10 mA cm^(-2).Moreover,the nanotube heterojunction arrays endows V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF with outstanding stability in long-term catalytic processes,as confirmed by the continuous chronopotentiom-etry tests at current densities of 10 mA cm^(-2) for 100 h.展开更多
The overall photocatalytic CO_(2) reduction reaction(OPCRR)that can directly convert CO_(2) and H_(2)O into fuels represents a promising renewable energy conversion technology.As a typical redox reaction,the OPCRR inv...The overall photocatalytic CO_(2) reduction reaction(OPCRR)that can directly convert CO_(2) and H_(2)O into fuels represents a promising renewable energy conversion technology.As a typical redox reaction,the OPCRR involves two half-reactions:the CO_(2) reduction half-reaction(CRHR)and the water oxidation half-reaction(WOHR).Generally,both half-reactions can be promoted by adjusting the wettability of catalysts.However,there is a contradiction in wettability requirements for the two half-reactions.Specifically,CRHR prefers a hydrophobic surface that can accumulate more CO_(2) molecules on the active sites,ensuring the appropriate ratio of gas-phase(CO_(2))to liquid-phase(H_(2)O)reactants.Conversely,the WOHR prefers a hydrophilic surface that can promote the departure of the gaseous product(O_(2))from the catalyst surface,preventing isolation between active sites and the reactant(H_(2)O).Here,we successfully reconciled the contradictory wettability requirements for the CRHR and WOHR by creating an alternately hydrophobic catalyst.This was achieved through a selectively hydrophobic modification method and a charge-transfer-control strategy.Consequently,the collaboratively promoted CRHR and WOHR led to a significantly enhanced OPCRR with a solar-to-fuel conversion efficiency of 0.186%.Notably,in ethanol production,the catalyst exhibited a 10.64-fold increase in generation rate(271.44μmol g^(-1)h~(-1))and a 4-fold increase in selectivity(55.77%)compared to the benchmark catalyst.This innovative approach holds great potential for application in universal overall reactions involving gas participation.展开更多
Designing efficient and long-lasting non-metal electrocatalysts is an urgent task for addressing the issue of kinetic hysteresis in electrochemical oxidation reactions.The bimetallic hydroxides,catalyzing the oxygen e...Designing efficient and long-lasting non-metal electrocatalysts is an urgent task for addressing the issue of kinetic hysteresis in electrochemical oxidation reactions.The bimetallic hydroxides,catalyzing the oxygen evolution reaction(OER),have significant research potential because hydroxide reconstruction to generate an active phase is a remarkable advantage.Herein,the complete reconstruction of ultrathin CoNi(OH)_(2) nanosheets was achieved by embedding Ag nanoparticles into the hydroxide to induce a spontaneous redox reaction(SRR),forming heterojunction Ag@CoNi(OH)_(2) for bifunctional hydrolysis.Theoretical calculations and in situ Raman and ex situ characterizations revealed that the inductive effect of the Ag cation redistributed the charge to promote phase transformation to highly activate Ag-modified hydroxides.The Co-Ni dual sites in Co/NiOOH serve as novel active sites for optimizing the intermediates,thereby weakening the barrier formed by OOH^*.Ag@CoNi(OH)_(2) required a potential of 1.55 V to drive water splitting at a current density of 10 mA cm^(-2),with nearly 98.6% Faraday efficiency.Through ion induction and triggering of electron regulation in the OER via the synergistic action of the heterogeneous interface and surface reconstruction,this strategic design can overcome the limited capacity of bimetallic hydroxides and bridge the gap between the basic theory and industrialization of water decomposition.展开更多
Urea oxidation reaction(UOR)is proposed as an exemplary half-reaction in renewable energy applications because of its low thermodynamical potential.However,challenges persist due to sluggish reaction kinetics and comp...Urea oxidation reaction(UOR)is proposed as an exemplary half-reaction in renewable energy applications because of its low thermodynamical potential.However,challenges persist due to sluggish reaction kinetics and complex by-products separation.To this end,we introduce the lattice oxygen oxidation mechanism(LOM),propelling a novel UOR route using a modified CoFe layered double hydroxide(LDH)catalyst termed CFRO-7.Theoretical calculations and in-situ characterizations highlight the activated lattice oxygen(O_(L))within CFRO-7 as pivotal sites for UOR,optimizing the reaction pathway and accelerating the kinetics.For the urea overall electrolysis application,the LOM route only requires a low voltage of 1.54 V to offer a high current of 100 mA cm^(-2) for long-term utilization(>48 h).Importantly,the by-product NCO^(-)−is significantly suppressed,while the CO_(2)2/N_(2) separation is efficiently achieved.This work proposed a pioneering paradigm,invoking the LOM pathway in urea electrolysis to expedite reaction dynamics and enhance product selectivity.展开更多
Electrocatalytic water splitting is crucial for H2generation via hydrogen evolution reaction(HER)but subject to the sluggish dynamics of oxygen evolution reaction(OER).In this work,single Fe atomdoped MoS_(2)nanosheet...Electrocatalytic water splitting is crucial for H2generation via hydrogen evolution reaction(HER)but subject to the sluggish dynamics of oxygen evolution reaction(OER).In this work,single Fe atomdoped MoS_(2)nanosheets(SFe-DMNs)were prepared based on the high-throughput density functional theory(DFT)calculation screening.Due to the synergistic effect between Fe atom and MoS_(2)and optimized intermediate binding energy,the SFe-DMNs could deliver outstanding activity for both HER and OER.When assembled into a two-electrode electrolytic cell,the SFe-DMNs could achieve the current density of 50 mA cm^(-2)at a low cell voltage of 1.55 V under neutral condition.These results not only confirmed the effectiveness of high-throughput screening,but also revealed the excellent activity and thus the potential applications in fuel cells of SFe-DMNs.展开更多
Electrocatalytic overall water splitting(OWS),a pivotal approach in addressing the global energy crisis,aims to produce hydrogen and oxygen.However,most of the catalysts in powder form are adhesively bounding to the e...Electrocatalytic overall water splitting(OWS),a pivotal approach in addressing the global energy crisis,aims to produce hydrogen and oxygen.However,most of the catalysts in powder form are adhesively bounding to the electrodes,resulting in catalyst detachment by bubble generation and other uncertain interference,and eventually reducing the OWS performance.To surmount this challenge,we synthesized a hybrid material of Co_(3)S_(4)-pyrolysis lotus fiber(labeled as Co_(3)S_(4)-p LF)textile by hydrothermal and hightemperature pyrolysis processes for electrocatalytic OWS.Owing to the natural LF textile exposing the uniformly distributed functional groups(AOH,ANH_(2),etc.)to anchor Co_(3)S_(4)nanoparticles with hierarchical porous structure and outstanding hydrophily,the hybrid Co_(3)S_(4)-p LF catalyst shows low overpotentials at 10 m A cm^(-2)(η_(10,HER)=100 m Vη_(10,OER)=240 mV)alongside prolonged operational stability during electrocatalytic reactions.Theoretical calculations reveal that the electron transfer from p LF to Co_(3)S_(4)in the hybrid Co_(3)S_(4)-p LF is beneficial to the electrocatalytic process.This work will shed light on the development of nature-inspired carbon-based materials in hybrid electrocatalysts for OWS.展开更多
This article examines the relationship between headwear design and overall clothing styling,emphasizing the importance of headwear in conveying personal style and cultural identity.It traces the evolution of Chinese a...This article examines the relationship between headwear design and overall clothing styling,emphasizing the importance of headwear in conveying personal style and cultural identity.It traces the evolution of Chinese and Western headwear throughout history,highlighting the interplay between headwear and the wearer's personal charac-teristics,life events,and cultural background.The article concludes by emphasizing that headwear design is not only a reflection of fashion,but also a manifestation of cultural depth and individuality.展开更多
The sluggish kinetics of both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)generate the large overpotential in water electrolysis and thus high-cost hydrogen production.Here,multidimensional nanop...The sluggish kinetics of both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)generate the large overpotential in water electrolysis and thus high-cost hydrogen production.Here,multidimensional nanoporous interpenetrating-phase FeNiZn alloy and FeNi_(3)intermetallic heterostructure is in situ constructed on NiFe foam(FeNiZn/FeNi_(3)@NiFe)by dealloying protocol.Coupling with the eminent synergism among specific constituents and the highly efficient mass transport from integrated porous backbone,FeNiZn/FeNi_(3)@NiFe depicts exceptional bifunctional activities for water splitting with extremely low overpotentials toward OER and HER(η_(1000)=367/245 mV)as well as the robust durability during the 400 h testing in alkaline solution.The as-built water electrolyzer with FeNiZn/FeNi_(3)@NiFe as both anode and cathode exhibits record-high performances for sustainable hydrogen output in terms of much lower cell voltage of 1.759 and 1.919 V to deliver the current density of 500 and 1000 mA cm^(-2)as well long working lives.Density functional theory calculations disclose that the interface interaction between FeNiZn alloy and FeNi_(3)intermetallic generates the modulated electron structure state and optimized intermediate chemisorption,thus diminishing the energy barriers for hydrogen production in water splitting.With the merits of fine performances,scalable fabrication,and low cost,FeNiZn/FeNi_(3)@NiFe holds prospective application potential as the bifunctional electrocatalyst for water splitting.展开更多
Electrocatalytic oxygen evolution reaction(OER)has been recognized as the bottleneck of overall water splitting,which is a promising approach for sustainable production of H_(2).Transition metal(TM)hydroxides are the ...Electrocatalytic oxygen evolution reaction(OER)has been recognized as the bottleneck of overall water splitting,which is a promising approach for sustainable production of H_(2).Transition metal(TM)hydroxides are the most conventional and classical non-noble metal-based electrocatalysts for OER,while TM basic salts[M^(2+)(OH)_(2-x)(A_(m^(-))_(x/m),A=CO_(3)^(2−),NO_(3)^(−),F^(−),Cl^(−)]consisting of OH−and another anion have drawn extensive research interest due to its higher catalytic activity in the past decade.In this review,we summarize the recent advances of TM basic salts and their application in OER and further overall water splitting.We categorize TM basic salt-based OER pre-catalysts into four types(CO_(3)^(2−),NO_(3)^(−),F^(−),Cl^(−)according to the anion,which is a key factor for their outstanding performance towards OER.We highlight experimental and theoretical methods for understanding the structure evolution during OER and the effect of anion on catalytic performance.To develop bifunctional TM basic salts as catalyst for the practical electrolysis application,we also review the present strategies for enhancing its hydrogen evolution reaction activity and thereby improving its overall water splitting performance.Finally,we conclude this review with a summary and perspective about the remaining challenges and future opportunities of TM basic salts as catalysts for water electrolysis.展开更多
Rational design of bifunctional electrocatalysts for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)with excellent activity and stability is of great significance,since overall water splitting is a ...Rational design of bifunctional electrocatalysts for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)with excellent activity and stability is of great significance,since overall water splitting is a promising technology for sustainable conversion of clean energy.However,most electrocatalysts do not simultaneously possess optimal HER/OER activities and their electrical conductivities are intrinsically low,which limit the development of overall water splitting.In this paper,a strategy of electric field treatment is proposed and applied to Ni/Co_(3)O_(4) film to develop a novel bifunctional electrocatalyst.After treated by electric field,the conductive channels consisting of oxygen vacancies are formed in the Co_(3)O_(4) film,which remarkably reduces the resistance of the system by almost 2×10^(4) times.Meanwhile,the surface Ni metal electrode is partially oxidized to nickel oxide,which enhances the catalytic activity.The electric-field-treated Ni/Co_(3)O_(4) material exhibits super outstanding performance of HER,OER,and overall water splitting,and the catalytic activity is significantly superior to the state-of-the-art noble metal catalysts(Pt/C,RuO_(2),and RuO_(2)‖Pt/C couple).This work provides an effective and feasible method for the development of novel and efficient bifunctional electrocatalyst,which is also promising for wide use in the field of catalysis.展开更多
Despite of suitable band structures for harvesting solar light and driving water redox reactions,polymeric carbon nitride(PCN)has suffered from poor charge transfer ability and sluggish surface reaction kinetics,which...Despite of suitable band structures for harvesting solar light and driving water redox reactions,polymeric carbon nitride(PCN)has suffered from poor charge transfer ability and sluggish surface reaction kinetics,which limit its photocatalytic activity for water splitting.Herein,atomically dispersed Zn-coordinated three-dimensional(3D)sponge-like PCN(Zn-PCN)is synthesized through a novel intermediate coordination strategy.Advanced characterizations and theoretical calculations well evidence that Zn single atoms are coordinated and stabilized on PCN in the form of Zn-N_(6) configura-tion featured with an electron-deficient state.Such an electronic configuration has been demonstrated contributive to promoted electron excitation,accelerated charge separation and transfer as well as reduced water redox barriers.Further benefited from the abundant surface active sites derived from the 3D porous structure,Zn-PCN realizes visible-light photocatalysis for overall water splitting with H_(2) and O_(2) simultaneously evolved at a stoichiometric ratio of 2:1.This work brings new insights into the design of novel single-atom photocatalysts by deepening the understanding of electronic configurations and reactive sites favorable to excellent photocatalysis for water splitting and related solar energy conversion reactions.展开更多
Electrocatalytic water splitting using power generated from renewable energy to produce hydrogen has been considered as one of the more attractive approach to alleviate the problems of energy crisis and environmental ...Electrocatalytic water splitting using power generated from renewable energy to produce hydrogen has been considered as one of the more attractive approach to alleviate the problems of energy crisis and environmental pollution.One of the biggest challenges for the large-scale application of water electrolysis is the searching of the low cost electrocatalysts with high and stable activity toward both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).The well-developed porous features of materials synthesized from the earth abundant elements endow them with the enhanced mass transfer and improved electronic interconnection during electrochemical reactions,resulting in the excellent electrocatalytic performance for both OER and HER.Herein,this review focuses on the recent development of innovation strategies for the fabrication of porous non-noble-metal materials including heteroatom-doped carbon-based and transition metal(mainly Co,Ni,and Fe)-based materials as efficient electrocatalysts for overall water splitting.Specially,a detailed discussion of the structure–activity correlation gives an insight on the origin of the high electrocatalytic performance of porous materials obtained from different strategies,and provides guidance for future design and preparation of highly efficient electocatalysts based on non-precious carbon or metal materials for overall water splitting.展开更多
The development of stable electrocatalysts with high hydrogen and oxygen evolution reactions (HER and OER) activity in alkaline electrolytes is critical to renewable energy conversion technologies,such as electrochemi...The development of stable electrocatalysts with high hydrogen and oxygen evolution reactions (HER and OER) activity in alkaline electrolytes is critical to renewable energy conversion technologies,such as electrochemical water splitting.In this work,a novel strategy for engineering water splitting electrocatalysts in alkaline electrolyte was developed by synergistically coupling La-doped Ni Fe-layered double hydroxides (Ni Fe-LDH) nanosheets onto three-dimensional (3D) vertically aligned MXene nanosheets on macroporous nickel foam (NF) substrates (Ni Fe La-LDH/v-MXene/NF).The electrocatalytic performance of the prepared Ni Fe La-LDH/v-MXene/NF is enhanced by the synergy of strong electronic interaction among multiple metal centers and unique vertically aligned porous MXene with increased active surface area,accelerated reaction kinetics and improved water adsorption and dissociation ability.To reach the commercially required current density (500 m A cm^(-2)),the Ni Fe La-LDH/v-MXene/NF exhibits greatly reduced overpotentials of 233 and 255 m V for HER and OER,respectively,along with excellent durability.Moreover,an alkaline electrolyzer driven by Ni Fe La-LDH/v-MXene/NF delivers a lower cell voltage(1.71 V) compared with that of Pt/C-RuO_(2) couple to achieve the current density of 500 m A cm^(-2).展开更多
The design of efficient,stable,and economical electrocatalysts for oxygen and hydrogen evolution reaction(OER and HER)is a major challenge for overall water splitting.Herein,a hierarchical structured CoP/carbon nanofi...The design of efficient,stable,and economical electrocatalysts for oxygen and hydrogen evolution reaction(OER and HER)is a major challenge for overall water splitting.Herein,a hierarchical structured CoP/carbon nanofibers(CNFs)composite was successfully synthesized and its potential application as a high-efficiency bifunctional electrocatalyst for overall splitting water was evaluated.The synergetic effect of two-dimensional(2D)CoP nanosheets and on e-dimensi on al(1D)CNFs endowed the CoP/CNFs composites with abundant active sites and rapid electron and mass transport pathways,and thereby significantly improved the electrocatalytic performances.The optimized CoP/CNFs delivered a current density of 10 mA cm^(-2) at low overpotential of 325 mV for OER and 225 mV for HER.In the overall water splitting,CoP/CNFs achieved a low potential of 1.65 V at 10 mA cm^(-2).The facile strategy provided in the present work can facilitate the design and development of multifunctional non-noble metal catalysts for energy applications.展开更多
Rational coupling of hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) catalysts is extremely important for practical overall water splitting,but it is still challenging to construct such bifunctiona...Rational coupling of hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) catalysts is extremely important for practical overall water splitting,but it is still challenging to construct such bifunctional heterostructures.Herein,we present a metal-organic framework(MOF)-etching strategy to design free-standing and hierarchical hollow CoS_(2)-MoS_(2) heteronanosheet arrays for both HER and OER.Resulting from the controllable etching of MOF by MoO_(4)^(2-) and in-situ sulfuration,the obtained CoS_(2)-MoS_(2) possesses abundant heterointerfaces with modulated local charge distribution,which promote water dissociation and rapid electrocatalytic kinetics.Moreover,the two-dimensional hollow array architecture can not only afford rich surface-active sites,but also facilitate the penetration of electrolytes and the release of evolved H_(2)/O_(2) bubbles.Consequently,the engineered CoS_(2)-MoS_(2) heterostructure exhibits small overpotentials of 82 mV for HER and 266 mV for OER at 10 mA cm^(-2).The corresponding alkaline electrolyzer affords a cell voltage of 1.56 V at 10 mA cm^(-2) to boost overall water splitting,along with robust durability over 24 h, even surpassing the benchmark electrode couple composed of IrO_(2) and Pt/C The present work may provide valuable insights for developing MOF-derived heterogeneous electrocatalysts with tailored interface/surface structure for widespread application in catalysis and other energyrelated areas.展开更多
Designing readily available and highly active electrocatalysts for water splitting is essential for renewable energy technologies.Here we present the construction of FeCo-FeCoP@C hollow nanocubes encapsulated in nitro...Designing readily available and highly active electrocatalysts for water splitting is essential for renewable energy technologies.Here we present the construction of FeCo-FeCoP@C hollow nanocubes encapsulated in nitrogen-doped carbon nanocages(FeCo-FeCoP@C@NCCs) through controlled carbonization and subsequent phosphorization of a Prussian blue analogue.With stronger electronic interaction and hollow structure,the as-obtained FeCo-FeCoP@C@NCCs material requires small overpotentials of 91 mV and280 mV to deliver 10 mA cm^(-2) in 1 M KOH toward hydrogen and oxygen evolution,respectively.More importantly,applying this material for overall water splitting,it only requires 1.64 V to afford10 mA cm^(-2) and exhibits impressively durability over 40 h without obvious performance decay.The present approach inspires potentials for the controllable synthesis of multi-component catalysts for practical applications.展开更多
Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Her...Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Herein,hollow oxygen deficiency-enriched NiFe_(2)O_(4) is synthesized by pyrolytic FeNi bimetallic MOF.The defects of rGO during carbonization can act as nucleation sites for FeNi particles.After nucleation and N doping,the FeNi particles were served as catalysts for the deposition of dissolved carbon in the defects of the N/rGO.These deposited carbon,like a bridge,connect N/rGO and hollow oxygen deficiency-enriched NiFe_(2)O_(4) together,which giving full play to the advantages of N/rGO in fast electron transfer,thereby improving its catalytic activity.The resultant NiFe_(2)O_(4)@N/rGO-800 exhibits a low overpotential of 252 mV at 20 mA cm^(-2) for OER and 157 mV at 10 mA cm^(-2) for HER in 1 M KOH,respectively.When used as bifunctional electrodes for overall water splitting,it also shows low cell voltage of 1.60 V and 1.67 V at 10 and 20 mA cm^(-2),respectively.展开更多
The electronic structures and properties of electrocatalysts,which depend on the physicochemical structure and metallic element components,could significantly affect their electrocatalytic performance and their future...The electronic structures and properties of electrocatalysts,which depend on the physicochemical structure and metallic element components,could significantly affect their electrocatalytic performance and their future applications in Zn-air battery(ZAB)and overall water splitting(OWS).Here,by combining vacancies and heterogeneous interfacial engineering,three-dimensional(3D)core-shell NiCoP/NiO heterostructures with dominated oxygen vacancies have been controllably in-situ grown on carbon cloth for using as highly efficient electrocatalysts toward hydrogen and oxygen electrochemical reactions.Theoretical calculation and electrochemical results manifest that the hybridization of NiCoP core with NiO shell produces a strong synergistic electronic coupling effect.The oxygen vacancy can enable the emergence of new electronic states within the band gap,crossing the Fermi levels of the two spin components and optimizing the local electronic structure.Besides,the hierarchical core-shell NiCoP/NiO nanoarrays also endow the catalysts with multiple exposed active sites,faster mass transfer behavior,optimized electronic strutures and improved electrochemical performance during ZAB and OWS applications.展开更多
Developing high-performance noble metal-free and free-standing catalytic electrodes are crucial for overall water splitting. Here, nickel sulfide（NiS） and nickel selenide（Ni Se） are synthesized on nickel foam（NF...Developing high-performance noble metal-free and free-standing catalytic electrodes are crucial for overall water splitting. Here, nickel sulfide（NiS） and nickel selenide（Ni Se） are synthesized on nickel foam（NF） with a one-pot solvothermal method and directly used as free-standing electrodes for efficiently catalyzing hydrogen evolution reaction（HER） and oxygen evolution reaction（OER） in alkaline solution.In virtue of abundant active sites, the NiS/NF and the NiS e/NF electrodes can deliver a current density of 10 m A cmat only 123 m V, 137 m V for HER and 222 m V, 271 m V for OER. Both of the hierarchical NiS/NF and Ni Se/NF electrodes can serve as anodes and cathodes in electrocatalytic overall watersplitting and can achieve a current density of 10 m A cmwith an applied voltage of.59 V and 1.69 V,respectively. The performance of as-obtained NiS/NF||NiS/NF is even close to that of the noble metalbased Pt/C/NF||IrO/NF system.展开更多
Simultaneously realizing improved activity and stability of acidic oxygen evolution reaction(OER) electrocatalysts is highly promising for developing cost-effective sustainable energy in the splitting of water techniq...Simultaneously realizing improved activity and stability of acidic oxygen evolution reaction(OER) electrocatalysts is highly promising for developing cost-effective sustainable energy in the splitting of water technique.Herein,we report iridium nanocrystals embedded into 3D conductive clothes(Ir-NCT/CC) as a low iridium electrocatalyst realizing ultrahigh acidic OER activity and robust stability.The well-designed Ir-NCT/CC requires a low overpotential of 202 mV to reach the current density of 10 mA cm^(-2)with a high mass activity of 1754 A g^(-1).Importantly,in acidic overall water splitting,Ir-NCT/CC merely delivers a cell voltage of 1.469 V at a typical current density of 10 mA cm^(-2)and also maintains robust durability under continuous operation.We identify that a low working voltage drives the formation of a highly stable amorphous IrOxactive phase over the surface of Ir nanocrystals(surface heterojunction IrOx/Ir-NCT) during operating conditions,which contributes to an effective and durable OER process.展开更多
基金supported by the National Natural Science Foundation of China under Grant No.52072196,52002200,52102106,52202262,22379081,22379080Major Basic Research Program of Natural Science Foundation of Shandong Province under Grant No.ZR2020zD09the Natural Science Foundation of Shandong Province under Grant No.ZR2020QE063,ZR202108180009,ZR2023QE059.
文摘The development of highly active,stable and inexpensive electrocatalysts for hydrogen production by defects and morphology engineering remains a great challenge.Herein,S vacancies-rich Ni_(3)S_(2)@Cu_(2)S nan-otube heterojunction arrays were in-situ grown on copper foam(V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF)for efficient electrocatalytic overall water splitting.With the merits of nanotube arrays and efficient electronic mod-ulation drived by the OD vacancy defect and 2D heterojunction defect,the resultant V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF electrocatalyst exhibits excellent electrocatalytic activity with a low overpotential of 47 mV for the hydrogen evolution reaction(HER)at 10 mA cm^(-2) current density,and 263 mV for the oxygen evolution reaction(OER)at 50 mA cm^(-2) current density,as well as a cell voltage of 1.48 V at 10 mA cm^(-2).Moreover,the nanotube heterojunction arrays endows V_(s)-Ni_(3)S_(2)@V_(s)-Cu_(2)S NHAs/CF with outstanding stability in long-term catalytic processes,as confirmed by the continuous chronopotentiom-etry tests at current densities of 10 mA cm^(-2) for 100 h.
基金financially supported by the National Natural Science Foundation of China(22378204,22008121,51790492)the National Outstanding Youth Science Fund Project of National Natural Science Foundation of China(T2125004)+1 种基金the Funding of NJUST(No.TSXK2022D002)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX23_0454)。
文摘The overall photocatalytic CO_(2) reduction reaction(OPCRR)that can directly convert CO_(2) and H_(2)O into fuels represents a promising renewable energy conversion technology.As a typical redox reaction,the OPCRR involves two half-reactions:the CO_(2) reduction half-reaction(CRHR)and the water oxidation half-reaction(WOHR).Generally,both half-reactions can be promoted by adjusting the wettability of catalysts.However,there is a contradiction in wettability requirements for the two half-reactions.Specifically,CRHR prefers a hydrophobic surface that can accumulate more CO_(2) molecules on the active sites,ensuring the appropriate ratio of gas-phase(CO_(2))to liquid-phase(H_(2)O)reactants.Conversely,the WOHR prefers a hydrophilic surface that can promote the departure of the gaseous product(O_(2))from the catalyst surface,preventing isolation between active sites and the reactant(H_(2)O).Here,we successfully reconciled the contradictory wettability requirements for the CRHR and WOHR by creating an alternately hydrophobic catalyst.This was achieved through a selectively hydrophobic modification method and a charge-transfer-control strategy.Consequently,the collaboratively promoted CRHR and WOHR led to a significantly enhanced OPCRR with a solar-to-fuel conversion efficiency of 0.186%.Notably,in ethanol production,the catalyst exhibited a 10.64-fold increase in generation rate(271.44μmol g^(-1)h~(-1))and a 4-fold increase in selectivity(55.77%)compared to the benchmark catalyst.This innovative approach holds great potential for application in universal overall reactions involving gas participation.
基金supported by the Inner Mongolia R&D Program Plan(2021ZD0042,2021EEDSCXSFQZD006)the National Natural Science Foundation of China(21902123)the Natural Science Basic Research Program of Shaanxi(2023-JC-ZD-22)。
文摘Designing efficient and long-lasting non-metal electrocatalysts is an urgent task for addressing the issue of kinetic hysteresis in electrochemical oxidation reactions.The bimetallic hydroxides,catalyzing the oxygen evolution reaction(OER),have significant research potential because hydroxide reconstruction to generate an active phase is a remarkable advantage.Herein,the complete reconstruction of ultrathin CoNi(OH)_(2) nanosheets was achieved by embedding Ag nanoparticles into the hydroxide to induce a spontaneous redox reaction(SRR),forming heterojunction Ag@CoNi(OH)_(2) for bifunctional hydrolysis.Theoretical calculations and in situ Raman and ex situ characterizations revealed that the inductive effect of the Ag cation redistributed the charge to promote phase transformation to highly activate Ag-modified hydroxides.The Co-Ni dual sites in Co/NiOOH serve as novel active sites for optimizing the intermediates,thereby weakening the barrier formed by OOH^*.Ag@CoNi(OH)_(2) required a potential of 1.55 V to drive water splitting at a current density of 10 mA cm^(-2),with nearly 98.6% Faraday efficiency.Through ion induction and triggering of electron regulation in the OER via the synergistic action of the heterogeneous interface and surface reconstruction,this strategic design can overcome the limited capacity of bimetallic hydroxides and bridge the gap between the basic theory and industrialization of water decomposition.
基金supported by Fundamental Research Funds for the Central Universities(B220202062)supported by Key Program of National Natural Science Foundation of China(92047201,92047303,52102237)+1 种基金National Science Funds for Creative Research Groups of China(51421006)supported by Postdoctoral Science Foundations of China and Jiangsu Province(2021M690861,2022T150183,2021K065A)。
文摘Urea oxidation reaction(UOR)is proposed as an exemplary half-reaction in renewable energy applications because of its low thermodynamical potential.However,challenges persist due to sluggish reaction kinetics and complex by-products separation.To this end,we introduce the lattice oxygen oxidation mechanism(LOM),propelling a novel UOR route using a modified CoFe layered double hydroxide(LDH)catalyst termed CFRO-7.Theoretical calculations and in-situ characterizations highlight the activated lattice oxygen(O_(L))within CFRO-7 as pivotal sites for UOR,optimizing the reaction pathway and accelerating the kinetics.For the urea overall electrolysis application,the LOM route only requires a low voltage of 1.54 V to offer a high current of 100 mA cm^(-2) for long-term utilization(>48 h).Importantly,the by-product NCO^(-)−is significantly suppressed,while the CO_(2)2/N_(2) separation is efficiently achieved.This work proposed a pioneering paradigm,invoking the LOM pathway in urea electrolysis to expedite reaction dynamics and enhance product selectivity.
基金supported by the Research Funds of Institute of Zhejiang University-Quzhou(IZQ2023RCZX032)the Natural Science Foundation of Guangdong Province(2022A1515010185)+1 种基金the Fundamental Research Funds for the Central Universities(FRF-TP-20-005A3)partially supported by the Special Funds for Postdoctoral Research at Tsinghua University(100415017)。
文摘Electrocatalytic water splitting is crucial for H2generation via hydrogen evolution reaction(HER)but subject to the sluggish dynamics of oxygen evolution reaction(OER).In this work,single Fe atomdoped MoS_(2)nanosheets(SFe-DMNs)were prepared based on the high-throughput density functional theory(DFT)calculation screening.Due to the synergistic effect between Fe atom and MoS_(2)and optimized intermediate binding energy,the SFe-DMNs could deliver outstanding activity for both HER and OER.When assembled into a two-electrode electrolytic cell,the SFe-DMNs could achieve the current density of 50 mA cm^(-2)at a low cell voltage of 1.55 V under neutral condition.These results not only confirmed the effectiveness of high-throughput screening,but also revealed the excellent activity and thus the potential applications in fuel cells of SFe-DMNs.
基金supported by the Scientific Research Foundation of Hunan Provincial Education Department,China(22B0893)the Scientific Research Foundation of Hunan Provincial Education Department,China(20A060)。
文摘Electrocatalytic overall water splitting(OWS),a pivotal approach in addressing the global energy crisis,aims to produce hydrogen and oxygen.However,most of the catalysts in powder form are adhesively bounding to the electrodes,resulting in catalyst detachment by bubble generation and other uncertain interference,and eventually reducing the OWS performance.To surmount this challenge,we synthesized a hybrid material of Co_(3)S_(4)-pyrolysis lotus fiber(labeled as Co_(3)S_(4)-p LF)textile by hydrothermal and hightemperature pyrolysis processes for electrocatalytic OWS.Owing to the natural LF textile exposing the uniformly distributed functional groups(AOH,ANH_(2),etc.)to anchor Co_(3)S_(4)nanoparticles with hierarchical porous structure and outstanding hydrophily,the hybrid Co_(3)S_(4)-p LF catalyst shows low overpotentials at 10 m A cm^(-2)(η_(10,HER)=100 m Vη_(10,OER)=240 mV)alongside prolonged operational stability during electrocatalytic reactions.Theoretical calculations reveal that the electron transfer from p LF to Co_(3)S_(4)in the hybrid Co_(3)S_(4)-p LF is beneficial to the electrocatalytic process.This work will shed light on the development of nature-inspired carbon-based materials in hybrid electrocatalysts for OWS.
文摘This article examines the relationship between headwear design and overall clothing styling,emphasizing the importance of headwear in conveying personal style and cultural identity.It traces the evolution of Chinese and Western headwear throughout history,highlighting the interplay between headwear and the wearer's personal charac-teristics,life events,and cultural background.The article concludes by emphasizing that headwear design is not only a reflection of fashion,but also a manifestation of cultural depth and individuality.
基金supported by National Science Foundation of China(52201254)Shandong Province(ZR2020MB090,ZR2020QE012)the project of“20 Items of University”of Jinan(202228046)。
文摘The sluggish kinetics of both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)generate the large overpotential in water electrolysis and thus high-cost hydrogen production.Here,multidimensional nanoporous interpenetrating-phase FeNiZn alloy and FeNi_(3)intermetallic heterostructure is in situ constructed on NiFe foam(FeNiZn/FeNi_(3)@NiFe)by dealloying protocol.Coupling with the eminent synergism among specific constituents and the highly efficient mass transport from integrated porous backbone,FeNiZn/FeNi_(3)@NiFe depicts exceptional bifunctional activities for water splitting with extremely low overpotentials toward OER and HER(η_(1000)=367/245 mV)as well as the robust durability during the 400 h testing in alkaline solution.The as-built water electrolyzer with FeNiZn/FeNi_(3)@NiFe as both anode and cathode exhibits record-high performances for sustainable hydrogen output in terms of much lower cell voltage of 1.759 and 1.919 V to deliver the current density of 500 and 1000 mA cm^(-2)as well long working lives.Density functional theory calculations disclose that the interface interaction between FeNiZn alloy and FeNi_(3)intermetallic generates the modulated electron structure state and optimized intermediate chemisorption,thus diminishing the energy barriers for hydrogen production in water splitting.With the merits of fine performances,scalable fabrication,and low cost,FeNiZn/FeNi_(3)@NiFe holds prospective application potential as the bifunctional electrocatalyst for water splitting.
基金supported by the financial support from Natural Science Foundation of China(Nos.21871065,22209129 and 22071038)High-Level Innovation and Entrepreneurship(QCYRCXM-2022-123)+1 种基金support from the“Young Talent Support Plan”of Xi’an Jiaotong University(HG6J024)“Young Talent Lift Plan”of Xi’an city(095920221352).
文摘Electrocatalytic oxygen evolution reaction(OER)has been recognized as the bottleneck of overall water splitting,which is a promising approach for sustainable production of H_(2).Transition metal(TM)hydroxides are the most conventional and classical non-noble metal-based electrocatalysts for OER,while TM basic salts[M^(2+)(OH)_(2-x)(A_(m^(-))_(x/m),A=CO_(3)^(2−),NO_(3)^(−),F^(−),Cl^(−)]consisting of OH−and another anion have drawn extensive research interest due to its higher catalytic activity in the past decade.In this review,we summarize the recent advances of TM basic salts and their application in OER and further overall water splitting.We categorize TM basic salt-based OER pre-catalysts into four types(CO_(3)^(2−),NO_(3)^(−),F^(−),Cl^(−)according to the anion,which is a key factor for their outstanding performance towards OER.We highlight experimental and theoretical methods for understanding the structure evolution during OER and the effect of anion on catalytic performance.To develop bifunctional TM basic salts as catalyst for the practical electrolysis application,we also review the present strategies for enhancing its hydrogen evolution reaction activity and thereby improving its overall water splitting performance.Finally,we conclude this review with a summary and perspective about the remaining challenges and future opportunities of TM basic salts as catalysts for water electrolysis.
基金supported by the program B for Outstanding PhD candidate of Nanjing University.
文摘Rational design of bifunctional electrocatalysts for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)with excellent activity and stability is of great significance,since overall water splitting is a promising technology for sustainable conversion of clean energy.However,most electrocatalysts do not simultaneously possess optimal HER/OER activities and their electrical conductivities are intrinsically low,which limit the development of overall water splitting.In this paper,a strategy of electric field treatment is proposed and applied to Ni/Co_(3)O_(4) film to develop a novel bifunctional electrocatalyst.After treated by electric field,the conductive channels consisting of oxygen vacancies are formed in the Co_(3)O_(4) film,which remarkably reduces the resistance of the system by almost 2×10^(4) times.Meanwhile,the surface Ni metal electrode is partially oxidized to nickel oxide,which enhances the catalytic activity.The electric-field-treated Ni/Co_(3)O_(4) material exhibits super outstanding performance of HER,OER,and overall water splitting,and the catalytic activity is significantly superior to the state-of-the-art noble metal catalysts(Pt/C,RuO_(2),and RuO_(2)‖Pt/C couple).This work provides an effective and feasible method for the development of novel and efficient bifunctional electrocatalyst,which is also promising for wide use in the field of catalysis.
基金This work was supported by the National Key Research and Development Program of China(2018YFB1502003)the National Natural Science Foundation of China(52225606,21875183,52172248)+2 种基金the“Fundamental Research Funds for the Central Universities”the Natural Science Basic Research Program of Shaanxi Province(2019JCW-10)“The Youth Innovation Team of Shaanxi Universities”.
文摘Despite of suitable band structures for harvesting solar light and driving water redox reactions,polymeric carbon nitride(PCN)has suffered from poor charge transfer ability and sluggish surface reaction kinetics,which limit its photocatalytic activity for water splitting.Herein,atomically dispersed Zn-coordinated three-dimensional(3D)sponge-like PCN(Zn-PCN)is synthesized through a novel intermediate coordination strategy.Advanced characterizations and theoretical calculations well evidence that Zn single atoms are coordinated and stabilized on PCN in the form of Zn-N_(6) configura-tion featured with an electron-deficient state.Such an electronic configuration has been demonstrated contributive to promoted electron excitation,accelerated charge separation and transfer as well as reduced water redox barriers.Further benefited from the abundant surface active sites derived from the 3D porous structure,Zn-PCN realizes visible-light photocatalysis for overall water splitting with H_(2) and O_(2) simultaneously evolved at a stoichiometric ratio of 2:1.This work brings new insights into the design of novel single-atom photocatalysts by deepening the understanding of electronic configurations and reactive sites favorable to excellent photocatalysis for water splitting and related solar energy conversion reactions.
基金This work was supported by the National Natural Science Foundation of China(21573115,21875118)the Natural Science Foundation of Tianjin(19JCZDJC37700).
文摘Electrocatalytic water splitting using power generated from renewable energy to produce hydrogen has been considered as one of the more attractive approach to alleviate the problems of energy crisis and environmental pollution.One of the biggest challenges for the large-scale application of water electrolysis is the searching of the low cost electrocatalysts with high and stable activity toward both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).The well-developed porous features of materials synthesized from the earth abundant elements endow them with the enhanced mass transfer and improved electronic interconnection during electrochemical reactions,resulting in the excellent electrocatalytic performance for both OER and HER.Herein,this review focuses on the recent development of innovation strategies for the fabrication of porous non-noble-metal materials including heteroatom-doped carbon-based and transition metal(mainly Co,Ni,and Fe)-based materials as efficient electrocatalysts for overall water splitting.Specially,a detailed discussion of the structure–activity correlation gives an insight on the origin of the high electrocatalytic performance of porous materials obtained from different strategies,and provides guidance for future design and preparation of highly efficient electocatalysts based on non-precious carbon or metal materials for overall water splitting.
基金supported by the National Natural Science Foundation of China(NSFC,51772040)the Doctoral Startup Foundation of Dalian University(1201012)。
文摘The development of stable electrocatalysts with high hydrogen and oxygen evolution reactions (HER and OER) activity in alkaline electrolytes is critical to renewable energy conversion technologies,such as electrochemical water splitting.In this work,a novel strategy for engineering water splitting electrocatalysts in alkaline electrolyte was developed by synergistically coupling La-doped Ni Fe-layered double hydroxides (Ni Fe-LDH) nanosheets onto three-dimensional (3D) vertically aligned MXene nanosheets on macroporous nickel foam (NF) substrates (Ni Fe La-LDH/v-MXene/NF).The electrocatalytic performance of the prepared Ni Fe La-LDH/v-MXene/NF is enhanced by the synergy of strong electronic interaction among multiple metal centers and unique vertically aligned porous MXene with increased active surface area,accelerated reaction kinetics and improved water adsorption and dissociation ability.To reach the commercially required current density (500 m A cm^(-2)),the Ni Fe La-LDH/v-MXene/NF exhibits greatly reduced overpotentials of 233 and 255 m V for HER and OER,respectively,along with excellent durability.Moreover,an alkaline electrolyzer driven by Ni Fe La-LDH/v-MXene/NF delivers a lower cell voltage(1.71 V) compared with that of Pt/C-RuO_(2) couple to achieve the current density of 500 m A cm^(-2).
基金supported by the National Natural Science Foundation of China(22072138,U1904215 and 21802033)the Program for Innovative Research Team in Science and Technology in University of Henan Province(20IRTSTHN003).
文摘The design of efficient,stable,and economical electrocatalysts for oxygen and hydrogen evolution reaction(OER and HER)is a major challenge for overall water splitting.Herein,a hierarchical structured CoP/carbon nanofibers(CNFs)composite was successfully synthesized and its potential application as a high-efficiency bifunctional electrocatalyst for overall splitting water was evaluated.The synergetic effect of two-dimensional(2D)CoP nanosheets and on e-dimensi on al(1D)CNFs endowed the CoP/CNFs composites with abundant active sites and rapid electron and mass transport pathways,and thereby significantly improved the electrocatalytic performances.The optimized CoP/CNFs delivered a current density of 10 mA cm^(-2) at low overpotential of 325 mV for OER and 225 mV for HER.In the overall water splitting,CoP/CNFs achieved a low potential of 1.65 V at 10 mA cm^(-2).The facile strategy provided in the present work can facilitate the design and development of multifunctional non-noble metal catalysts for energy applications.
基金the financial support by the National Natural Science Foundation of China(NSFC) Grants(51702295)。
文摘Rational coupling of hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) catalysts is extremely important for practical overall water splitting,but it is still challenging to construct such bifunctional heterostructures.Herein,we present a metal-organic framework(MOF)-etching strategy to design free-standing and hierarchical hollow CoS_(2)-MoS_(2) heteronanosheet arrays for both HER and OER.Resulting from the controllable etching of MOF by MoO_(4)^(2-) and in-situ sulfuration,the obtained CoS_(2)-MoS_(2) possesses abundant heterointerfaces with modulated local charge distribution,which promote water dissociation and rapid electrocatalytic kinetics.Moreover,the two-dimensional hollow array architecture can not only afford rich surface-active sites,but also facilitate the penetration of electrolytes and the release of evolved H_(2)/O_(2) bubbles.Consequently,the engineered CoS_(2)-MoS_(2) heterostructure exhibits small overpotentials of 82 mV for HER and 266 mV for OER at 10 mA cm^(-2).The corresponding alkaline electrolyzer affords a cell voltage of 1.56 V at 10 mA cm^(-2) to boost overall water splitting,along with robust durability over 24 h, even surpassing the benchmark electrode couple composed of IrO_(2) and Pt/C The present work may provide valuable insights for developing MOF-derived heterogeneous electrocatalysts with tailored interface/surface structure for widespread application in catalysis and other energyrelated areas.
基金financial support from the National Natural Science Foundation of China (21471039, 21571043, 21671047, 21673273, 21872163 and 21871065)the Natural Science Foundation of Heilongjiang Province (B2015001)the Guangdong Provincial Key Laboratory of Energy Materials for Electric Power (No. 2018B030322001)。
文摘Designing readily available and highly active electrocatalysts for water splitting is essential for renewable energy technologies.Here we present the construction of FeCo-FeCoP@C hollow nanocubes encapsulated in nitrogen-doped carbon nanocages(FeCo-FeCoP@C@NCCs) through controlled carbonization and subsequent phosphorization of a Prussian blue analogue.With stronger electronic interaction and hollow structure,the as-obtained FeCo-FeCoP@C@NCCs material requires small overpotentials of 91 mV and280 mV to deliver 10 mA cm^(-2) in 1 M KOH toward hydrogen and oxygen evolution,respectively.More importantly,applying this material for overall water splitting,it only requires 1.64 V to afford10 mA cm^(-2) and exhibits impressively durability over 40 h without obvious performance decay.The present approach inspires potentials for the controllable synthesis of multi-component catalysts for practical applications.
基金financially supported by the National Natural Science Foundation of China(Nos.21878231,21676202 and 51603145)Natural Science Foundation of Tianjin(Nos.19JCZDJC37300 and 17JCZDJC38100)supported by the Science and Technology Plans of Tianjin(Nos.17PTSYJC00040 and 18PTSYJC00180)。
文摘Bimetallic metal organic framework(MOF)as a precursor to prepare catalysts with bifunctional catalytic activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)attracts more and more attention.Herein,hollow oxygen deficiency-enriched NiFe_(2)O_(4) is synthesized by pyrolytic FeNi bimetallic MOF.The defects of rGO during carbonization can act as nucleation sites for FeNi particles.After nucleation and N doping,the FeNi particles were served as catalysts for the deposition of dissolved carbon in the defects of the N/rGO.These deposited carbon,like a bridge,connect N/rGO and hollow oxygen deficiency-enriched NiFe_(2)O_(4) together,which giving full play to the advantages of N/rGO in fast electron transfer,thereby improving its catalytic activity.The resultant NiFe_(2)O_(4)@N/rGO-800 exhibits a low overpotential of 252 mV at 20 mA cm^(-2) for OER and 157 mV at 10 mA cm^(-2) for HER in 1 M KOH,respectively.When used as bifunctional electrodes for overall water splitting,it also shows low cell voltage of 1.60 V and 1.67 V at 10 and 20 mA cm^(-2),respectively.
基金financially supported by the National Natural Science Foundation of China(No.22179014,21603019)program for the Hundred Talents Program of Chongqing University。
文摘The electronic structures and properties of electrocatalysts,which depend on the physicochemical structure and metallic element components,could significantly affect their electrocatalytic performance and their future applications in Zn-air battery(ZAB)and overall water splitting(OWS).Here,by combining vacancies and heterogeneous interfacial engineering,three-dimensional(3D)core-shell NiCoP/NiO heterostructures with dominated oxygen vacancies have been controllably in-situ grown on carbon cloth for using as highly efficient electrocatalysts toward hydrogen and oxygen electrochemical reactions.Theoretical calculation and electrochemical results manifest that the hybridization of NiCoP core with NiO shell produces a strong synergistic electronic coupling effect.The oxygen vacancy can enable the emergence of new electronic states within the band gap,crossing the Fermi levels of the two spin components and optimizing the local electronic structure.Besides,the hierarchical core-shell NiCoP/NiO nanoarrays also endow the catalysts with multiple exposed active sites,faster mass transfer behavior,optimized electronic strutures and improved electrochemical performance during ZAB and OWS applications.
基金support from the National Natural Science Foundation of China(nos.51722207 and 51372131)973 Program of China(nos.2015CB932500 and 2014CB932401)+2 种基金Beijing Nova Program(no.Z161100004916099)the International Collaboration Project of Tsinghua University Initiative Scientific Research Program(no.20173080001)Chinese Postdoctoral Science Foundation(no.2015M570092)
文摘Developing high-performance noble metal-free and free-standing catalytic electrodes are crucial for overall water splitting. Here, nickel sulfide（NiS） and nickel selenide（Ni Se） are synthesized on nickel foam（NF） with a one-pot solvothermal method and directly used as free-standing electrodes for efficiently catalyzing hydrogen evolution reaction（HER） and oxygen evolution reaction（OER） in alkaline solution.In virtue of abundant active sites, the NiS/NF and the NiS e/NF electrodes can deliver a current density of 10 m A cmat only 123 m V, 137 m V for HER and 222 m V, 271 m V for OER. Both of the hierarchical NiS/NF and Ni Se/NF electrodes can serve as anodes and cathodes in electrocatalytic overall watersplitting and can achieve a current density of 10 m A cmwith an applied voltage of.59 V and 1.69 V,respectively. The performance of as-obtained NiS/NF||NiS/NF is even close to that of the noble metalbased Pt/C/NF||IrO/NF system.
基金supported by the National Natural Science Foundation of China(12205300 and 12135012)the Natural Science Foundation of Anhui Province(2208085QA28 and 2208085J01)。
文摘Simultaneously realizing improved activity and stability of acidic oxygen evolution reaction(OER) electrocatalysts is highly promising for developing cost-effective sustainable energy in the splitting of water technique.Herein,we report iridium nanocrystals embedded into 3D conductive clothes(Ir-NCT/CC) as a low iridium electrocatalyst realizing ultrahigh acidic OER activity and robust stability.The well-designed Ir-NCT/CC requires a low overpotential of 202 mV to reach the current density of 10 mA cm^(-2)with a high mass activity of 1754 A g^(-1).Importantly,in acidic overall water splitting,Ir-NCT/CC merely delivers a cell voltage of 1.469 V at a typical current density of 10 mA cm^(-2)and also maintains robust durability under continuous operation.We identify that a low working voltage drives the formation of a highly stable amorphous IrOxactive phase over the surface of Ir nanocrystals(surface heterojunction IrOx/Ir-NCT) during operating conditions,which contributes to an effective and durable OER process.
