The recently demonstrated methods for cooling and trapping diatomic molecules offer new possibilities for precision searches in fundamental physical theories.Here,we propose to study the variations of the fine-structu...The recently demonstrated methods for cooling and trapping diatomic molecules offer new possibilities for precision searches in fundamental physical theories.Here,we propose to study the variations of the fine-structure constant(α=e^(2)/(hc)) and the proton-to-electron mass ratio(μ=m_(p)/m_(e)) with time by taking advantage of the nearly degenerate rovibrational levels in the electronic states of the magnesium fluoride(MgF) molecule.Specifically,due to the cancellation between the fine-structure splitting and the rovibrational intervals in the different MgF natural isotopes,a degeneracy occurs for A^(2)П_(3/2)(v'=0,J'=18.5,-) and A^(2)П_(1/2)(v "=0,J" =20.5,-).We find that using the nearly degenerate energy level of such states can be 104 times more sensitive than using a pure rotational transition to measure the variations of α and μ.To quantify the small gap between A^(2)П_(3/2)(v'=0,J'=18.5,-) and A^(2)П_(1/2)(v "=0,J" =20.5,-),special transitions of choice are feasible:X^(2)Σ_(1/2)~+(v=0,J=19.5,+) to A^(2)П_(3/2)(v'=0,J'=18.5,-) and X^(2)Σ_(1/2)~+(v=0.J=19.5,+)to A^(2)П_(1/2)(v "=0,J" =20.5,-).In addition,we estimate the frequency uncertainties caused by the narrow linewidth,Zeeman shift,Stark shift,Doppler broadening and blackbody radiation.展开更多
As H-and J-aggregation receive more and more attention in the research of organic solar cells(OSCs),especially in small molecular systems,deep understanding of aggregation behavior is needed to guide the design of con...As H-and J-aggregation receive more and more attention in the research of organic solar cells(OSCs),especially in small molecular systems,deep understanding of aggregation behavior is needed to guide the design of conjugated small molecular structure and the fabrication process of OSC device.For this end,this review is written.Here,the review firstly introduced the basic information about H-and J-aggregation of conjugated small molecules in OSCs.Then,the characteristics of H-and J-aggregation and the methods to identify them were summarized.Next,it reviewed the research progress of H-and J-aggregation of conjugated small molecules in OSCs,including the factors influencing H-and J-aggregation in thin film and the effects of H-and J-aggregation on OPV performance.展开更多
Aqueous Zn-ion batteries(AZIBs)have attracted increasing attention in next-generation energy storage systems due to their high safety and economic.Unfortunately,the side reactions,dendrites and hydrogen evolution effe...Aqueous Zn-ion batteries(AZIBs)have attracted increasing attention in next-generation energy storage systems due to their high safety and economic.Unfortunately,the side reactions,dendrites and hydrogen evolution effects at the zinc anode interface in aqueous electrolytes seriously hinder the application of aqueous zinc-ion batteries.Here,we report a critical solvation strategy to achieve reversible zinc electrochemistry by introducing a small polar molecule acetonitrile to form a“catcher”to arrest active molecules(bound water molecules).The stable solvation structure of[Zn(H_(2)O)_(6)]^(2+)is capable of maintaining and completely inhibiting free water molecules.When[Zn(H_(2)O)_(6)]^(2+)is partially desolvated in the Helmholtz outer layer,the separated active molecules will be arrested by the“catcher”formed by the strong hydrogen bond N-H bond,ensuring the stable desolvation of Zn^(2+).The Zn||Zn symmetric battery can stably cycle for 2250 h at 1 mAh cm^(-2),Zn||V_(6)O_(13) full battery achieved a capacity retention rate of 99.2%after 10,000 cycles at 10 A g^(-1).This paper proposes a novel critical solvation strategy that paves the route for the construction of high-performance AZIBs.展开更多
In the last few years,research on advanced ultrafast photonic devices has attracted great interest from laser physicists.As a semiconductor material with excellent nonlinear saturation absorption characteristics,Ga As...In the last few years,research on advanced ultrafast photonic devices has attracted great interest from laser physicists.As a semiconductor material with excellent nonlinear saturation absorption characteristics,Ga As has been used in solidstate and fiber lasers as a mode-locker.However,the pulse widths that have been reported in the searchable published literature are all long and the shortest is tens of picoseconds.Femtosecond pulse widths,desired for a variety of applications,have not yet been reported in Ga As-based pulsed lasers.In this work,we further explore the nonlinear characteristics of Ga As that has been magnetron sputtered onto the surface of a tapered fiber and its application in the generation of femtosecond lasing via effective dispersion optimization and nonlinearity management.With the enhanced interaction between evanescent waves and Ga As nanosheets,mode-locked soliton pulses as short as 830 fs are generated at repetition rates of 4.64 MHz.As far as we know,this is the first time that femtosecond-level pulses have been generated with a Ga As-based saturable absorber.In addition,soliton molecules,including in the dual-pulse state,are also realized under stronger pumping.This work demonstrates that Ga As-based photonic devices have good application prospects in effective polymorphous ultrashort pulsed laser generation.展开更多
The tensile strain in inorganic perovskite films induced by thermal annealing is one of the primary factors contributing to the inefficiency and instability of inorganic perovskite solar cells(IPSCs),which reduces the...The tensile strain in inorganic perovskite films induced by thermal annealing is one of the primary factors contributing to the inefficiency and instability of inorganic perovskite solar cells(IPSCs),which reduces the defect formation energy.Here,a flexible molecule 5-maleimidovaleric acid(5-MVA)was introduced as a strain buffer to release the residual strain of CsPbI_(2.85)Br_(0.15)perovskite.Maleic anhydride and carboxyl groups in 5-MVA interact strongly with the uncoordinated Pb^(2+)through Lewis acid-base reaction,thus tightly“pull”the perovskite lattice.The in-between soft carbon chain increased the structural flexibility of CsPbI_(2.85)Br_(0.15)perovskite materials,which effectively relieved the intrinsic internal strain of CsPbI_(2.85)Br_(0.15),resisted the corrosion of external strain,and also reduced the formation of defects such as VIand Pb0.In addition,the introduction of 5-MVA improved crystal quality,passivated residual defects,and narrowed energy level barriers.Eventually,power conversion efficiency(PCE)of NiOxbased inverted IPSCs increased from 19.25%to 20.82%with the open-circuit voltage enhanced from 1.164 V to 1.230 V.The release of strain also improved the stability of CsPbI_(2.85)Br_(0.15)perovskite films and devices.展开更多
Aqueous potassium-ion batteries(APIBs),recognized as safe and reliable new energy devices,are considered as one of the alternatives to traditional batteries.Layered MnO_(2),serving as the main cathode,exhibits a lower...Aqueous potassium-ion batteries(APIBs),recognized as safe and reliable new energy devices,are considered as one of the alternatives to traditional batteries.Layered MnO_(2),serving as the main cathode,exhibits a lower specific capacity in aqueous electrolytes compared to organic systems and operates through a different reaction mechanism.The application of highly conductive graphene may effectively enhance the capacity of APIBs but could complicate the potassium storage environment.In this study,a MnO_(2) cathode pre-intercalated with K~+ions and grown on graphene(KMO@rGO) was developed using the microwave hydrothermal method for APIBs.KMO@rGO achieved a specific capacity of 90 mA h g^(-1) at a current density of 0.1 A g^(-1),maintaining a capacity retention rate of>90% after 5000 cycles at 5 A g^(-1).In-situ and exsitu characterization techniques revealed the energy-storage mechanism of KMO@rGO:layered MnO_(2)traps a large amount of "dead" water molecules during K~+ions removal.However,the introduction of graphene enables these water molecules to escape during K~+ ions insertion at the cathode.The galvanostatic intermittent titration technique and density functional theory confirmed that KMO@rGO has a higher K~+ions migration rate than MnO_(2).Therefore,the capacity of this cathode depends on the interaction between dead water and K~+ions during the energy-storage reaction.The optimal structural alignment between layered MnO_(2) and graphene allows electrons to easily flow into the external circuit.Rapid charge compensation forces numerous low-solvent K~+ions to displace interlayer dead water,enhancing the capacity.This unique reaction mechanism is unprecedented in other aqueous battery studies.展开更多
Inverted perovskite solar cells have gained prominence in industrial advancement due to their easy fabrication,low hysteresis effects,and high stability.Despite these advantages,their efficiency is currently limited b...Inverted perovskite solar cells have gained prominence in industrial advancement due to their easy fabrication,low hysteresis effects,and high stability.Despite these advantages,their efficiency is currently limited by excessive defects and poor carrier transport at the perovskite-electrode interface,particularly at the buried interface between the perovskite and transparent conductive oxide(TCO).Recent efforts in the perovskite community have focused on designing novel self-assembled molecules(SAMs)to improve the quality of the buried interface.However,a notable gap remains in understanding the regulation of atomic-scale interfacial properties of SAMs between the perovskite and TCO interfaces.This understanding is crucial,particularly in terms of identifying chemically active anchoring groups.In this study,we used the star SAM([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)as the base structure to investigate the defect passivation effects of eight common anchoring groups at the perovskite-TCO interface.Our findings indicate that the phosphonic and boric acid groups exhibit notable advantages.These groups fulfill three key criteria:they provide the greatest potential for defect passivation,exhibit stable adsorption with defects,and exert significant regulatory effects on interface dipoles.Ionized anchoring groups exhibit enhanced passivation capabilities for defect energy levels due to their superior Lewis base properties,which effectively neutralize local charges near defects.Among various defect types,iodine vacancies are the easiest to passivate,whereas iodine-substituted lead defects are the most challenging to passivate.Our study provides comprehensive theoretical insights and inspiration for the design of anchoring groups in SAMs,contributing to the ongoing development of more efficient inverted perovskite solar cells.展开更多
Recently,many encouraging experimental advances have been achieved in ternary hydrides superconductors under high pressure.However,the extreme pressure required is indeed a challenge for practical application,which pr...Recently,many encouraging experimental advances have been achieved in ternary hydrides superconductors under high pressure.However,the extreme pressure required is indeed a challenge for practical application,which promotes a further exploration for high temperature(T_(c))superconductors at relatively low pressure.Herein,we performed a systematic theoretical investigation on a series of ternary hydrides with stoichiometry AX_(2)H_(8),which is constructed by interacting molecular XH_(4)(X=B,C,and N)into the fcc metal A lattice under low pressure of 0-150 GPa.We uncovered five compounds which are dynamically stable below 100 GPa,e.g.,AcB_(2)H_(8)(25 GPa),LaB_(2)H_(8)(40 GPa),RbC_(2)H_(8)(40 GPa),CSC_(2)H_(8)(60 GPa),and SrC_(2)H_(8)(65 GPa).Among them,AcB_(2)H_(8),which is energetically stable above 2.5 GPa,exhibits the highest Tcof 32 K at 25 GPa.The superconductivity originates mainly from the coupling between the electron of Ac atoms and the associated low-frequency phonons,distinct from the previous typical hydrides with H-derived superconductivity.Our results shed light on the future exploration of superconductivity among ternary compounds at low pressure.展开更多
The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chrom...The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chromatography-time of flight mass spectrography(GC-TOF-MS)to study the effects of microorganisms and small molecular metabolites on the quality of ham in different processing years.The results showed that the dominant bacteria phyla of Nuodeng ham in different processing years were Proteobacteria and Firmicutes,the dominant fungi phyla were Ascomycota and Basidiomycota,while Staphylococcus and Aspergillus were the dominant bacteria and fungi of Nuodeng ham,respectively.Totally,252 kinds of small molecular metabolites were identified from Nuodeng ham in different processing years,and 12 different metabolites were screened through multivariate statistical analysis.Further metabolic pathway analysis showed that 23 metabolic pathways were related to ham fermentation,of which 8 metabolic pathways had significant effects on ham fermentation(Impact>0.01,P<0.05).The content of L-proline,phenyllactic acid,L-lysine,carnosine,taurine,D-proline,betaine and creatine were significantly positively correlated with the relative abundance of Staphylococcus and Serratia,but negatively correlated with the relative abundance of Halomonas,Aspergillus and Yamadazyma.展开更多
The proper bandgap and exceptional photostability enable CsPbI_(3) as a potential candidate for indoor photovoltaics(IPVs),but indoor power conversion efficiency(PCE) is impeded by serious nonradiative recombination s...The proper bandgap and exceptional photostability enable CsPbI_(3) as a potential candidate for indoor photovoltaics(IPVs),but indoor power conversion efficiency(PCE) is impeded by serious nonradiative recombination stemming from challenges in incomplete DMAPbI_(3) conversion and lattice structure distortion.Here,the coplanar symmetric structu re of hexyl sulfide(HS) is employed to functionalize the CsPbI_(3) layer for fabricating highly efficient IPVs.The hydrogen bond between HS and DMAI promotes the conversion of DMAPbI_(3) to CsPbI_(3),while the copianar symmetric structure enhances crystalline order.Simultaneously,surface sulfidation during HS-induced growth results in the in situ formation of PbS,spontaneously creating a CsPbI_(3) N-P homojunction to enhance band alignment and carrier mobility.As a result,the CsPbI_(3)&HS devices achieve an impressive indoor PCE of 39.90%(P_(in):334.6 μW cm^(-2),P_(out):133.5 μW cm^(-2)) under LED@2968 K,1062 lux,and maintain over 90% initial PCE for 800 h at ^(3)0% air ambient humidity.展开更多
A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA Hamiltonian.This set was augmented with diffuse functions ...A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA Hamiltonian.This set was augmented with diffuse functions to describe electrons farther away from the nuclei adequately.Using the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were calculated.The addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular properties.For atomization energies,a similar observation emerges when considering spin-orbit couplings.With the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental values.Performance evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.展开更多
建立了一种在温和条件下,用可见光催化合成一系列3,4-二氢异喹啉-1(2H)-酮及其衍生物的方法。该方法在室温条件下,以2-烯丙基-N-甲氧基苯甲酰胺为模板底物,以碘化钾作为光催化剂,25 W 460 nm的蓝色LED灯照射下,合成一系列3,4-二氢异喹啉...建立了一种在温和条件下,用可见光催化合成一系列3,4-二氢异喹啉-1(2H)-酮及其衍生物的方法。该方法在室温条件下,以2-烯丙基-N-甲氧基苯甲酰胺为模板底物,以碘化钾作为光催化剂,25 W 460 nm的蓝色LED灯照射下,合成一系列3,4-二氢异喹啉-1(2H)-酮衍生物,最高产率可达到83%。该合成路径具有底物适用范围广、经济实用等特点,为3,4-二氢异喹啉-1(2H)-酮衍生物合成提供了一种经济简便的方法。展开更多
The yield stress of our newly developed electrorheological （ER） fluids consisting of dielectric nano-particles suspended in silicone oil reaches hundreds of kPa, which is orders of magnitude higher than that of conv...The yield stress of our newly developed electrorheological （ER） fluids consisting of dielectric nano-particles suspended in silicone oil reaches hundreds of kPa, which is orders of magnitude higher than that of conventional ones. We found that the polar molecules adsorbed on the particles play a decisive role in such new ER fluids. To explain this polar molecule dominated ER （PM-ER） effect a model is proposed based on the interaction of polar molecule-charge between the particles, where the local electric field is significantly enhanced and results in the polar molecules aligning in the direction of the electric field. The model can well explain the giant ER effect and a near-linear dependence of the yield stress on the electric field. The main effective factors for achieving high-performance PM-ER fluids are discussed. The PM-ER fluids with the yield stress higher than one MPa can be expected.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 12174115,11834003,and 91836103)。
文摘The recently demonstrated methods for cooling and trapping diatomic molecules offer new possibilities for precision searches in fundamental physical theories.Here,we propose to study the variations of the fine-structure constant(α=e^(2)/(hc)) and the proton-to-electron mass ratio(μ=m_(p)/m_(e)) with time by taking advantage of the nearly degenerate rovibrational levels in the electronic states of the magnesium fluoride(MgF) molecule.Specifically,due to the cancellation between the fine-structure splitting and the rovibrational intervals in the different MgF natural isotopes,a degeneracy occurs for A^(2)П_(3/2)(v'=0,J'=18.5,-) and A^(2)П_(1/2)(v "=0,J" =20.5,-).We find that using the nearly degenerate energy level of such states can be 104 times more sensitive than using a pure rotational transition to measure the variations of α and μ.To quantify the small gap between A^(2)П_(3/2)(v'=0,J'=18.5,-) and A^(2)П_(1/2)(v "=0,J" =20.5,-),special transitions of choice are feasible:X^(2)Σ_(1/2)~+(v=0,J=19.5,+) to A^(2)П_(3/2)(v'=0,J'=18.5,-) and X^(2)Σ_(1/2)~+(v=0.J=19.5,+)to A^(2)П_(1/2)(v "=0,J" =20.5,-).In addition,we estimate the frequency uncertainties caused by the narrow linewidth,Zeeman shift,Stark shift,Doppler broadening and blackbody radiation.
基金financially supported by the National Natural Science Foundation of China(52203024,22225504)the Shandong Provincial Natural Science Foundation(ZR2022QE135)+2 种基金the Youth Innovation Team Project of Shandong Provincial University(2023KJ330)the Qilu University of Technology strong base plan(2023PY001)Guangdong Provincial Key Laboratory of Catalysis(2020B121201002)。
文摘As H-and J-aggregation receive more and more attention in the research of organic solar cells(OSCs),especially in small molecular systems,deep understanding of aggregation behavior is needed to guide the design of conjugated small molecular structure and the fabrication process of OSC device.For this end,this review is written.Here,the review firstly introduced the basic information about H-and J-aggregation of conjugated small molecules in OSCs.Then,the characteristics of H-and J-aggregation and the methods to identify them were summarized.Next,it reviewed the research progress of H-and J-aggregation of conjugated small molecules in OSCs,including the factors influencing H-and J-aggregation in thin film and the effects of H-and J-aggregation on OPV performance.
基金supported by the National Natural Science Foundation of China(No.52272198 and 52002122)the Project funded by China Postdoctoral Science Foundation(No.2021M690947).
文摘Aqueous Zn-ion batteries(AZIBs)have attracted increasing attention in next-generation energy storage systems due to their high safety and economic.Unfortunately,the side reactions,dendrites and hydrogen evolution effects at the zinc anode interface in aqueous electrolytes seriously hinder the application of aqueous zinc-ion batteries.Here,we report a critical solvation strategy to achieve reversible zinc electrochemistry by introducing a small polar molecule acetonitrile to form a“catcher”to arrest active molecules(bound water molecules).The stable solvation structure of[Zn(H_(2)O)_(6)]^(2+)is capable of maintaining and completely inhibiting free water molecules.When[Zn(H_(2)O)_(6)]^(2+)is partially desolvated in the Helmholtz outer layer,the separated active molecules will be arrested by the“catcher”formed by the strong hydrogen bond N-H bond,ensuring the stable desolvation of Zn^(2+).The Zn||Zn symmetric battery can stably cycle for 2250 h at 1 mAh cm^(-2),Zn||V_(6)O_(13) full battery achieved a capacity retention rate of 99.2%after 10,000 cycles at 10 A g^(-1).This paper proposes a novel critical solvation strategy that paves the route for the construction of high-performance AZIBs.
基金Project supported by the National Natural Science Foundation of China(Grant No.12164030)Young Science and Technology Talents of Inner Mongolia,China(Grant No.NJYT22101)+1 种基金the Central Government Guides Local Science,the Technology Development Fund Projects(Grant No.2023ZY0005)the Science and Technology Plan Projects of Inner Mongolia Autonomous Region of China(Grant No.2023KYPT0012)。
文摘In the last few years,research on advanced ultrafast photonic devices has attracted great interest from laser physicists.As a semiconductor material with excellent nonlinear saturation absorption characteristics,Ga As has been used in solidstate and fiber lasers as a mode-locker.However,the pulse widths that have been reported in the searchable published literature are all long and the shortest is tens of picoseconds.Femtosecond pulse widths,desired for a variety of applications,have not yet been reported in Ga As-based pulsed lasers.In this work,we further explore the nonlinear characteristics of Ga As that has been magnetron sputtered onto the surface of a tapered fiber and its application in the generation of femtosecond lasing via effective dispersion optimization and nonlinearity management.With the enhanced interaction between evanescent waves and Ga As nanosheets,mode-locked soliton pulses as short as 830 fs are generated at repetition rates of 4.64 MHz.As far as we know,this is the first time that femtosecond-level pulses have been generated with a Ga As-based saturable absorber.In addition,soliton molecules,including in the dual-pulse state,are also realized under stronger pumping.This work demonstrates that Ga As-based photonic devices have good application prospects in effective polymorphous ultrashort pulsed laser generation.
基金financial support of National Key Research and Development Program of China(Grant No.2022YFB04200302)joint funds of National Natural Science Foundation of China(Grant No.62104115)+5 种基金National Natural Science Foundation of China(Grant No.U21A2072)Overseas Expertise Introduction Project for Discipline Innovation of Higher Education of China(Grant No.B16027)Key R&D Program of Hebei Province(No.19214301D)Yunnan Provincial Science and Technology Project at Southwest United Graduate School(No.202302A0370009)Haihe Laboratory of Sustainable Chemical TransformationsFundamental Research Funds for the Central Universities,Nankai University。
文摘The tensile strain in inorganic perovskite films induced by thermal annealing is one of the primary factors contributing to the inefficiency and instability of inorganic perovskite solar cells(IPSCs),which reduces the defect formation energy.Here,a flexible molecule 5-maleimidovaleric acid(5-MVA)was introduced as a strain buffer to release the residual strain of CsPbI_(2.85)Br_(0.15)perovskite.Maleic anhydride and carboxyl groups in 5-MVA interact strongly with the uncoordinated Pb^(2+)through Lewis acid-base reaction,thus tightly“pull”the perovskite lattice.The in-between soft carbon chain increased the structural flexibility of CsPbI_(2.85)Br_(0.15)perovskite materials,which effectively relieved the intrinsic internal strain of CsPbI_(2.85)Br_(0.15),resisted the corrosion of external strain,and also reduced the formation of defects such as VIand Pb0.In addition,the introduction of 5-MVA improved crystal quality,passivated residual defects,and narrowed energy level barriers.Eventually,power conversion efficiency(PCE)of NiOxbased inverted IPSCs increased from 19.25%to 20.82%with the open-circuit voltage enhanced from 1.164 V to 1.230 V.The release of strain also improved the stability of CsPbI_(2.85)Br_(0.15)perovskite films and devices.
基金financially supported by the Scientific and Technological Plan Project of Guizhou Province (Grant No. [2021]060)the Industry and Education Combination Innovation Platform of Intelligent Manufacturing and the Graduate Joint Training Base at Guizhou University (Grant No. 2020-520000-83-01-324061)the Guizhou Engineering Research Center for smart services (Grant No. 2203-520102-04-04-298868)。
文摘Aqueous potassium-ion batteries(APIBs),recognized as safe and reliable new energy devices,are considered as one of the alternatives to traditional batteries.Layered MnO_(2),serving as the main cathode,exhibits a lower specific capacity in aqueous electrolytes compared to organic systems and operates through a different reaction mechanism.The application of highly conductive graphene may effectively enhance the capacity of APIBs but could complicate the potassium storage environment.In this study,a MnO_(2) cathode pre-intercalated with K~+ions and grown on graphene(KMO@rGO) was developed using the microwave hydrothermal method for APIBs.KMO@rGO achieved a specific capacity of 90 mA h g^(-1) at a current density of 0.1 A g^(-1),maintaining a capacity retention rate of>90% after 5000 cycles at 5 A g^(-1).In-situ and exsitu characterization techniques revealed the energy-storage mechanism of KMO@rGO:layered MnO_(2)traps a large amount of "dead" water molecules during K~+ions removal.However,the introduction of graphene enables these water molecules to escape during K~+ ions insertion at the cathode.The galvanostatic intermittent titration technique and density functional theory confirmed that KMO@rGO has a higher K~+ions migration rate than MnO_(2).Therefore,the capacity of this cathode depends on the interaction between dead water and K~+ions during the energy-storage reaction.The optimal structural alignment between layered MnO_(2) and graphene allows electrons to easily flow into the external circuit.Rapid charge compensation forces numerous low-solvent K~+ions to displace interlayer dead water,enhancing the capacity.This unique reaction mechanism is unprecedented in other aqueous battery studies.
基金supported by the National Natural Science Foundation of China(Grant Nos.62321166653,22090044,and 12350410372).Calculations were performed in part at the high-performance computing center of Jilin University.
文摘Inverted perovskite solar cells have gained prominence in industrial advancement due to their easy fabrication,low hysteresis effects,and high stability.Despite these advantages,their efficiency is currently limited by excessive defects and poor carrier transport at the perovskite-electrode interface,particularly at the buried interface between the perovskite and transparent conductive oxide(TCO).Recent efforts in the perovskite community have focused on designing novel self-assembled molecules(SAMs)to improve the quality of the buried interface.However,a notable gap remains in understanding the regulation of atomic-scale interfacial properties of SAMs between the perovskite and TCO interfaces.This understanding is crucial,particularly in terms of identifying chemically active anchoring groups.In this study,we used the star SAM([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)as the base structure to investigate the defect passivation effects of eight common anchoring groups at the perovskite-TCO interface.Our findings indicate that the phosphonic and boric acid groups exhibit notable advantages.These groups fulfill three key criteria:they provide the greatest potential for defect passivation,exhibit stable adsorption with defects,and exert significant regulatory effects on interface dipoles.Ionized anchoring groups exhibit enhanced passivation capabilities for defect energy levels due to their superior Lewis base properties,which effectively neutralize local charges near defects.Among various defect types,iodine vacancies are the easiest to passivate,whereas iodine-substituted lead defects are the most challenging to passivate.Our study provides comprehensive theoretical insights and inspiration for the design of anchoring groups in SAMs,contributing to the ongoing development of more efficient inverted perovskite solar cells.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12074154,12174160,and 11722433)the funding from the Six Talent Peaks Project+1 种基金333 High-level Talents Project of Jiangsu Provincethe Innovation and Entrepreneurship Training Programme for University Students in Jiangsu Province(Grant No.202210320140Y)。
文摘Recently,many encouraging experimental advances have been achieved in ternary hydrides superconductors under high pressure.However,the extreme pressure required is indeed a challenge for practical application,which promotes a further exploration for high temperature(T_(c))superconductors at relatively low pressure.Herein,we performed a systematic theoretical investigation on a series of ternary hydrides with stoichiometry AX_(2)H_(8),which is constructed by interacting molecular XH_(4)(X=B,C,and N)into the fcc metal A lattice under low pressure of 0-150 GPa.We uncovered five compounds which are dynamically stable below 100 GPa,e.g.,AcB_(2)H_(8)(25 GPa),LaB_(2)H_(8)(40 GPa),RbC_(2)H_(8)(40 GPa),CSC_(2)H_(8)(60 GPa),and SrC_(2)H_(8)(65 GPa).Among them,AcB_(2)H_(8),which is energetically stable above 2.5 GPa,exhibits the highest Tcof 32 K at 25 GPa.The superconductivity originates mainly from the coupling between the electron of Ac atoms and the associated low-frequency phonons,distinct from the previous typical hydrides with H-derived superconductivity.Our results shed light on the future exploration of superconductivity among ternary compounds at low pressure.
基金supported by Major Science and Technology Projects of Yunnan Science and Technology Plan(2019ZG003)Yunnan Young and Middle-aged Academic and Technical Leader Reserve Talent Project(202105AC160068)。
文摘The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chromatography-time of flight mass spectrography(GC-TOF-MS)to study the effects of microorganisms and small molecular metabolites on the quality of ham in different processing years.The results showed that the dominant bacteria phyla of Nuodeng ham in different processing years were Proteobacteria and Firmicutes,the dominant fungi phyla were Ascomycota and Basidiomycota,while Staphylococcus and Aspergillus were the dominant bacteria and fungi of Nuodeng ham,respectively.Totally,252 kinds of small molecular metabolites were identified from Nuodeng ham in different processing years,and 12 different metabolites were screened through multivariate statistical analysis.Further metabolic pathway analysis showed that 23 metabolic pathways were related to ham fermentation,of which 8 metabolic pathways had significant effects on ham fermentation(Impact>0.01,P<0.05).The content of L-proline,phenyllactic acid,L-lysine,carnosine,taurine,D-proline,betaine and creatine were significantly positively correlated with the relative abundance of Staphylococcus and Serratia,but negatively correlated with the relative abundance of Halomonas,Aspergillus and Yamadazyma.
基金financial support from the Natural Science Foundation of Guizhou Province (Grant No. ZK 2024-087)Natural Science Foundation of China (no. 22005071)。
文摘The proper bandgap and exceptional photostability enable CsPbI_(3) as a potential candidate for indoor photovoltaics(IPVs),but indoor power conversion efficiency(PCE) is impeded by serious nonradiative recombination stemming from challenges in incomplete DMAPbI_(3) conversion and lattice structure distortion.Here,the coplanar symmetric structu re of hexyl sulfide(HS) is employed to functionalize the CsPbI_(3) layer for fabricating highly efficient IPVs.The hydrogen bond between HS and DMAI promotes the conversion of DMAPbI_(3) to CsPbI_(3),while the copianar symmetric structure enhances crystalline order.Simultaneously,surface sulfidation during HS-induced growth results in the in situ formation of PbS,spontaneously creating a CsPbI_(3) N-P homojunction to enhance band alignment and carrier mobility.As a result,the CsPbI_(3)&HS devices achieve an impressive indoor PCE of 39.90%(P_(in):334.6 μW cm^(-2),P_(out):133.5 μW cm^(-2)) under LED@2968 K,1062 lux,and maintain over 90% initial PCE for 800 h at ^(3)0% air ambient humidity.
基金the financial support of Conselho Nacional de Desenvolvimento Científico e Tecnológico and Coordenacao de Aperfeic oamento de Pessoal de Nível Superior (Brazilian Agencies)。
文摘A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA Hamiltonian.This set was augmented with diffuse functions to describe electrons farther away from the nuclei adequately.Using the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were calculated.The addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular properties.For atomization energies,a similar observation emerges when considering spin-orbit couplings.With the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental values.Performance evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.
文摘建立了一种在温和条件下,用可见光催化合成一系列3,4-二氢异喹啉-1(2H)-酮及其衍生物的方法。该方法在室温条件下,以2-烯丙基-N-甲氧基苯甲酰胺为模板底物,以碘化钾作为光催化剂,25 W 460 nm的蓝色LED灯照射下,合成一系列3,4-二氢异喹啉-1(2H)-酮衍生物,最高产率可达到83%。该合成路径具有底物适用范围广、经济实用等特点,为3,4-二氢异喹啉-1(2H)-酮衍生物合成提供了一种经济简便的方法。
文摘The yield stress of our newly developed electrorheological （ER） fluids consisting of dielectric nano-particles suspended in silicone oil reaches hundreds of kPa, which is orders of magnitude higher than that of conventional ones. We found that the polar molecules adsorbed on the particles play a decisive role in such new ER fluids. To explain this polar molecule dominated ER （PM-ER） effect a model is proposed based on the interaction of polar molecule-charge between the particles, where the local electric field is significantly enhanced and results in the polar molecules aligning in the direction of the electric field. The model can well explain the giant ER effect and a near-linear dependence of the yield stress on the electric field. The main effective factors for achieving high-performance PM-ER fluids are discussed. The PM-ER fluids with the yield stress higher than one MPa can be expected.
