The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor ...The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.展开更多
Structural engineering of Pt-based nanoalloys is crucial for the rational design and manufacturing of high-performance and low-cost electrocatalysts for hydrogen evolution reaction(HER).Here,we reported PtNi nanoparti...Structural engineering of Pt-based nanoalloys is crucial for the rational design and manufacturing of high-performance and low-cost electrocatalysts for hydrogen evolution reaction(HER).Here,we reported PtNi nanoparticles with a refined size of 2.71 nm and regular strains loaded on carbon black,synthesized using the high-temperature liquid shock(HTLS)method.This approach offers significant advantages over conventional synthesis methods,including high scalability,rapid reaction rates,and precise control over the size and shape of nanocrystals.Importantly,the synthesized PtNi electrocatalysts demonstrate outstanding catalytic activity and long-term stability for HER,achieving low overpotentials of 19 and 203 mV at current densities of 10 and 1000 mA/cm^(2),respectively.The superior performance can be attributed to the combination of a refined particle size,lattice strains,and synergistic effects between Pt and Ni.This rapid liquid-state synthesis demonstrated here holds great potential for scalable and industrial manufacturing of micro-/nano-catalysts.展开更多
Efficient alkaline hydrogen evolution reaction(HER)catalysts are critical for anion exchange membrane water electrolysis(AEMWE).However,the intrinsic scaling relationship between water dissociation and OH desorption f...Efficient alkaline hydrogen evolution reaction(HER)catalysts are critical for anion exchange membrane water electrolysis(AEMWE).However,the intrinsic scaling relationship between water dissociation and OH desorption fundamentally impedes designing catalysts requiring concurrent superior water dissociation and facile OH desorption.Here,we engineer a superhydrophilic Ru/Cr_(2)O_(3) heterostructured electrocatalyst through in situ confinement of Ru nanoparticles(5-10 nm)within a Cr_(2)O_(3) matrix.Acting as a Lewis acid,the Cr_(2)O_(3) component provides alternative sites for water dissociation,accelerating the Volmer step kinetics and downshifting the Ru d-band center via interfacial charge transfer,while simultaneously adsorbing OH-to form a surface-bound Lewis base that repels excess OH-from Ru sites,thereby suppressing hydroxyl over-adsorption.Concurrently,the superhydrophilic surface architecture promotes efficient hydrogen bubble release,thereby reducing mass transport resistance.As a result,the Ru/Cr_(2)O_(3) heterostructured electrocatalyst exhibits an ultralow overpotential of 36.7 mV at 10 mA cm^(-2) and a Tafel slope of 33.2 mV dec^(-1).Integrated into an AEMWE device,the electrode delivers500 mA cm^(-2) for 2000 h in 1.0 M KOH,underscoring its industrial viability(hydrogen production energy consumption per cubic meter(EW):3.94 kW h m^(-3);electricity-to-hydrogen energy conversion efficiency(η_(ETH)):89%@80℃).展开更多
Regulating the critical process of proton migration from water dissociation for boosting alkaline hydrogen evolution reaction(HER)remains a challenge.Herein,we propose an electrostatic attraction strategy to achieve t...Regulating the critical process of proton migration from water dissociation for boosting alkaline hydrogen evolution reaction(HER)remains a challenge.Herein,we propose an electrostatic attraction strategy to achieve the migration of a highly efficient hydrogen species to Pt sites over Pt/Co@NC,which is obtained through a facile calcination and electrodeposition method.It exhibits an outstanding geometric activity(η_(10)=31 m V),which surpasses the commercial 20 wt%Pt/C(η_(10)=37 mV).Moreover,the mass activity of Pt/Co@NC is 5.6 A mg_(Pt)^(-1) at-50 mV vs.RHE,which is 2.23 times higher than that of 20 wt%Pt/C.Experimental and theoretical results indicate that the work function of the outer carbon layer,which is changed by the introduction of the inner cobalt core,plays a crucial role in reversing the direction of electron migration between the carbon layer and Pt.The negatively charged Pt^(δ-)can spontaneously attract positively charged protons via the electrostatic interaction effect,thereby achieving the directional migration of hydrogen species.This work presents a strategy for designing advanced alkaline HER electrocatalysts by the electrostatic effect.展开更多
Regulating the microenvironment of the support enables precise control of electronic metal-support interactions(EMSI),boosting better catalytic activity of the metal species.However,the fundamental relationship betwee...Regulating the microenvironment of the support enables precise control of electronic metal-support interactions(EMSI),boosting better catalytic activity of the metal species.However,the fundamental relationship between support defect-induced EMSI modulation and the resulting catalytic performance enhancement still needs further elucidation.Herein,a nonequilibrium high-temperature shock(HTS)method,which combines rapid high-temperature heating at 1273 K for 30 s with liquid nitrogen quenching,was adopted to load uniform Pt nanoparticles onto the nitrogen vacancy-rich TiN support(Pt@TiNVN).The catalyst demonstrates a high mass activity of 15.99 A mgPt^(-1)at an overpotential of 100 mV for the hydrogen evolution reaction(HER)in acidic solution and exhibits long-term stability for 60 h at 200 mA cm^(-2).Detailed spectroscopic characterizations and theoretical calculations reveal that the generated nitrogen vacancies can effectively modulate the charge transfer between Pt nanoparticles and the TiN-VN support,leading to a downshifted d-band center of metallic Pt and optimized Pt-H bond strength.This nonequilibrium HTS approach offers new and valuable insights into designing advanced electrocatalysts by harnessing substrate defects to modulate the electronic states of loaded noble metals.展开更多
The hydrogen evolution reaction(HER)is crucial for hydrogen production and sustainable energy storage.Molybdenum disulfide(MoS_(2)),a representative transition metal dichalcogenides(TMDs),shows potential as an HER cat...The hydrogen evolution reaction(HER)is crucial for hydrogen production and sustainable energy storage.Molybdenum disulfide(MoS_(2)),a representative transition metal dichalcogenides(TMDs),shows potential as an HER catalyst but suffers from limited performance due to poor charge transfer and interfacial effects.Here,we report a salt-assisted chemical vapor deposition(CVD)method for synthesizing high-quality tungsten ditelluride(WTe_(2))with tunable morphologies using alkali halides(NaCl,KCl and LiCl).The prepared WTe_(2) nanoribbons and hexagonal nanosheets exhibit morphology-dependent electrical conductivity,with nanosheets showing superior performance.To evaluate WTe_(2) as a contact electrode,WTe_(2)−MoS_(2) heterostructures were fabricated and compared with graphene-MoS_(2) counterparts.The WTe_(2)−MoS_(2) heterostructure exhibits a superior Tafel slope of 111.57 mV/dec and an overpotential of 298 mV at-10 mA/cm^(2),significantly outperforming graphene-based electrodes.This improvement is attributed to the excellent conductivity of WTe_(2) and reduced interfacial Schottky barriers.Moreover,we systematically investigate the influence of WTe_(2) thickness on HER performance and assess the electrochemical durability and structural stability of the heterostructure,further confirming the effectiveness of WTe_(2) as a contact electrode for enhancing the HER activity of MoS_(2).This study offers a novel approach for enhancing the HER performance of MoS_(2) through controlled WTe_(2) growth and application as a contact electrode.Our findings provide valuable insights into the synthesis of high-quality WTe_(2) and broaden the potential applications of two-dimensional materials in energy catalysis.展开更多
The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative...The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative solution in a pure acidic system,but the catalyst layer in direct contact with the hydrated proton environment usually leads to H_(2)evolution dominating.Herein,we show that polydimethyldiallyl-ammonium-chloride-coated Ag(Ag@PDDA)electrode exhibits outstanding performance with a FE of 86%,a single-pass conversion of 72%,and a stability of 28 h for CO production in pure-acid MEA compared with ammonium poly(N-methyl-piperidine-co-pterphenyl)decorated Ag(Ag/QAPPT)and cetyltrimethylammonium bromide decorated Ag(Ag/CTAB).The in situ ATR-SEIRAS reveal that PDDA creates a positive charge-rich protective outer layer and an N-rich hybrid inner layer,which not only suppresses the migration of H+during the electrolysis process and blocks the direct contact between H2O and Ag catalyst,but also promotes the generation from CO_(2)to*COOH in a pure-acid system.This work highlights the importance of polyelectrolyte engineering in regulating the electrocatalytic interface and accelerates the development of proton exchange membrane CO_(2)electrolysis.展开更多
Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent meta...Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent metal hydroxides deposition and boost the hydrogen evolution reaction by adding a chelating agent,EDTA-Na_(4),that chelates with Mg^(2+)/Ca^(2+),thus inhibiting their deposition and gathering them near the cathode surface,resulting in breaking the ordered hydrogen bond networks of interfacial water and reducing the activation energy of water dissociation.Furthermore,hydrolysis of–COO^(-) also promoted water dissociation to produce more active*H and*OH near the electrode surface that in turn serves as a diffusion medium for*OH,accelerating mass transfer and enabling seawater electrolysis to exhibit a stable performance,which operates continuously at 100 mA cm^(-2)@2.20 V and 200 mA cm^(-2)@2.58 V for 400 h in the symmetric electrolyzer and 500 mA cm^(-2)@2.29 V for over 500 h in the asymmetric electrolyzer.This study provides a new perspective to address the issues of stable and scalable direct seawater electrolysis for practical green hydrogen production.展开更多
Defect engineering serves as a cornerstone in the design of high-effciency single-atom catalysts(SACs)for advanced electrocatalytic systems.This study demonstrates oxygen vacancy-induced near-zero-valent Pt SACs ancho...Defect engineering serves as a cornerstone in the design of high-effciency single-atom catalysts(SACs)for advanced electrocatalytic systems.This study demonstrates oxygen vacancy-induced near-zero-valent Pt SACs anchored on TiO2 for efficient hydrogen evolution reaction(HER).Synchrotron spectroscopy and density functional theory calculation reveal that oxygen vacancies create unconventional Pt-Ti coordination while strengthening electronic metal-support interactions.This facilitates substantial electron transfer from TiO2 to Pt,generating a near-zero-valent Pt state with elevated electron density.The modified electronic structure lowers the Pt d-band center,reducing hydrogen intermediate(*H)adsorption energy and optimizing HER kinetics.Moreover,ab initio molecular dynamics and in situ Raman spectra show that the negative charge accumulated at the Pt site promotes K^(+)enrichment at the interface,which enhances H-OH bond polarization and accelerates water dissociation kinetics.The resulting D-TiO_(2)/Pt SACs exhibit superior HER activity across acidic,neutral,and alkaline conditions,achieving low overpotentials of 40,57,and 60 mV at 10 mA cm^(-2),respectively.Additionally,its mass activities at the overpotential of 100 mV are 10.3,33.9,and 20.9 times higher that of Pt/C,respectively.This study shows the key role of defectmediated electronic engineering in tailoring SACs'valence states and catalytic functions,advancing sustainable hydrogen production through rational catalyst design.展开更多
Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru ...Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance.展开更多
Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this s...Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ synthesis.These~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt ions.This unique structure is beneficial for the hydrogen evolution reaction.The catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C catalysts.Mass activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.展开更多
The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alka...The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds.展开更多
Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to thei...Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial contexts.This review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable development.The initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent advancements.The subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active sites.Ultimately,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER.展开更多
Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transfor...Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transformation.Herein,we demonstrate that PtFeNiCoCu high-entropy alloy(HEA)nanocrystals can act as efficient cocatalysts for H_(2)evolution coupled with selective oxidation of cinnamyl alcohol to cinnamaldehyde by cubic cadmium sulfide(CdS)quantum dots(QDs)with uniform sizes of 4.0±0.5 nm.HEA nanocrystals were prepared via a simple solvothermal approach,and were successfully integrated with CdS QDs by an electrostatic self-assembly method to construct HEA/CdS composites.The optimized HEA/CdS sample presented an enhanced photocatalytic H_(2)production rate of 7.15 mmol g^(-1)h^(-1),which was 13 times that of pure CdS QDs.Moreover,a cinnamyl alcohol conversion of 96.2%with cinnamaldehyde selectivity of 99.5%was achieved after photoreaction for 3 h.The integration of HEA with CdS QDs extended the optical absorption edge from 475 to 484 nm.From d-band center analysis,Pt atoms in the HEA are the active sites for H_(2)evolution,exhibiting higher catalytic activity than pure Pt.Meanwhile,the band structure of the CdS QDs enables the oxidative transformation of cinnamyl alcohol to cinnamaldehyde with high selectivity.Moreover,femtosecond transient absorption spectroscopy shows that HEA can significantly promote the separation of photogenerated carriers in CdS,which is vital for achieving enhanced photocatalytic activity.This work inspires atomic-level design of photocatalytic materials for coordinated production of green energy carriers and value-added products.展开更多
As hydrogen energy technologies gain momentum,the role of renewable energy in facilitating sustainable hydrogen production is becoming increasingly critical.As a hydrogen production method,water electrolysis has attra...As hydrogen energy technologies gain momentum,the role of renewable energy in facilitating sustainable hydrogen production is becoming increasingly critical.As a hydrogen production method,water electrolysis has attracted much attention from researchers due to its operational simplicity,the high purity of the hydrogen generated,and its potential for achieving zero carbon emissions throughout the process.Numerous studies has been manipulated on platinum(Pt)-based catalysts,which exhibit superior performance in hydrogen evolution reactions.Within this category,Pt nanoclusters stand out due to their unique attributes,such as quantum size effects and unique coordination environments.These features enable them to outperform both Pt metal atoms and nanoparticles in hydrogen evolution reactions regarding activity and stability.Here,we primarily delve into the reaction mechanisms underlying Pt nanocluster-based hydrogen catalysts,with particular emphasis on the interactions between the metal catalysts and their associated support materials.We provide an exhaustive summary of the strategies employed in the synthesis,the structural analyses conducted,and the performance metrics observed for Pt nanocluster catalysts when paired with various supporting materials.In closing,we explore the future potential and challenges facing Pt nanocluster-based catalysts in the context of industrial water electrolysis,along with emerging avenues for their design and optimization.展开更多
Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a...Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts.展开更多
The effects of seemingly inert alkali metal(AM)cations on the electrocatalytic activity of electrode materials towards reactions essential for energy provision have become the emphasis of substantial research efforts ...The effects of seemingly inert alkali metal(AM)cations on the electrocatalytic activity of electrode materials towards reactions essential for energy provision have become the emphasis of substantial research efforts in recent years.The hydrogen and oxygen evolution reactions during alkaline water electrolysis and the oxygen electro-reduction taking place in fuel cells are of particular importance.There is no universal theory explaining all the details of the AM cation effect in electrocatalysis.For example,it remains unclear how“spectator”AM-cations can change the kinetics of electrocatalytic reactions often more significantly than the modifications of the elec-trode structure and composition.This situation originates partly from a lack of systematic experimental and theoretical studies of this phenomenon.The present work exploits impedance spectroscopy to investigate the influence of the AM cations on the mechanism of the hydrogen evolution reaction at Pt microelectrodes.The activity follows the trend:Li^(+)≥Na^(+)≥K^(+)≥Cs^(+),where the highest activity corresponds to 0.1 M LiOH electrolytes at low overpotentials.We demonstrate that the nature of the AM cations also changes the relative contribution of the Volmer–Heyrovsky and Volmer–Tafel mechanisms to the overall reaction,with the former being more important for LiOH electrolytes.Our density functional theory-based thermodynamics and molecular dynamics calculations support these findings.展开更多
As a clean energy source,hydrogen plays a critical role in the global mission to achieve carbon neutrality.Among varied hydrogen production techniques,water electrolysis driven by clean energy,such as solar or wind en...As a clean energy source,hydrogen plays a critical role in the global mission to achieve carbon neutrality.Among varied hydrogen production techniques,water electrolysis driven by clean energy,such as solar or wind energy,is the most promising and viable option,with the advantages of celerity,high efficiency,cleanliness,and sustainability.However,this process necessitates a highly active and durable hydrogen evolution reaction(HER)catalyst to enhance the overall reaction efficiency.This article thoroughly reviews the recent development of electrocatalysts exhibiting high-performance HER.In particular,a comprehensive look at noble metals platinum(Pt),ruthenium(Ru),iridium(Ir),and non-noble metals,including sulfides,carbides,nitrides and phosphides is taken.Synthesis strategies,methods for enhancing performance,and the correlation between structure,composition,and catalytic performance are discussed.We also pay particular attention to density functional theory(DFT)calculations to reveal the mechanisms behind the improvement of HER performance.Finally,the critical challenges associated with electrochemical water splitting and propose coping strategies are presented.展开更多
Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrog...Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrogen content for electrochemical reactions are rarely reported.In this work,transition metal carbonitride MXenes incorporated with Pt-based electrocatalysts,ranging from single atoms to sub-nanometer dimensions,are explored for hydrogen evolution reaction(HER).The fabricated Pt clusters/MXene catalyst exhibits superior HER performance compared to the single-atom-incorporated MXene and commercial Pt/C catalyst in both acidic and alkaline electrolytes.The optimized sample shows low overpotentials of 28,65,and 154 mV at a current densities of 10,100,and 500 m A cm^(-2),a small Tafel slope of 29 m V dec^(-1),a high mass activity of 1203 mA mgPt^(-1)and an excellent turnover frequency of 6.1 s^(-1)in the acidic electrolyte.Density functional theory calculations indicate that this high performance can be attributed to the enhanced active sites,increased surface functional groups,faster charge transfer dynamics,and stronger electronic interaction between Pt and MXene,resulting in optimized hydrogen absorption/desorption toward better HER.This work demonstrates that MXenes with a high content of nitrogen may be promising candidates for various catalytic reactions by incorporating single atoms or clusters.展开更多
The issues of fossil energy shortage and environmental pollution caused by the excessive consumption of conventional fossil fuels necessitates the exploration of renewable and clean energy sources such as hydrogen,whi...The issues of fossil energy shortage and environmental pollution caused by the excessive consumption of conventional fossil fuels necessitates the exploration of renewable and clean energy sources such as hydrogen,which is viable alternative to traditional energy sources in view of its high energy density and nonpolluting nature.In this regard,photocatalytic technology powered by inexhaustible solar energy is an ideal hydrogen production method.The recently developed copper-and zinc-based multinary metal sulfide(MMS)semiconductor photocatalysts exhibit the advantages of suitable bandgap,wide light-harvesting range,and flexible elemental composition,thus possessing great potential for achieving considerable photocatalytic hydrogen evolution(PHE)performance.Despite great progress has been achieved,the current photocatalysts still cannot meet the commercial application demands,which highlights the mechanisms understanding and optimization strategies for efficient PHE.Herein,the basic mechanisms of PHE,and effective optimization strategies are firstly introduced.Afterwards,the research process and the performance of copper-and zinc-based MMS photocatalysts,are thoroughly reviewed.Finally,the unresolved issues,and challenges hindering the achievement of overall water splitting have been discussed.展开更多
文摘The efficiency and stability of catalysts for photocatalytic hydrogen evolution(PHE)are largely governed by the charge transfer behaviors across the heterojunction interfaces.In this study,CuO,a typical semiconductor featuring a broad spectral absorption range,is successfully employed as the electron acceptor to combine with CdS for constructing a S-scheme heterojunction.The optimized photocatalyst(CdSCuO2∶1)delivers an exceptional hydrogen evolution rate of 18.89 mmol/(g·h),4.15-fold higher compared with bare CdS.X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflection absorption spectroscopy(UV-vis DRS)confirmed the S-scheme band structure of the composites.Moreover,the surface photovoltage(SPV)and electron paramagnetic resonance(EPR)indicated that the photogenerated electrons and photogenerated holes of CdS-CuO2∶1 were respectively transferred to the conduction band(CB)of CdS with a higher reduction potential and the valence band(VB)of CuO with a higher oxidation potential under illumination,as expected for the S-scheme mechanism.Density-functional-theory calculations of the electron density difference(EDD)disclose an interfacial electric field oriented from CdS to CuO.This built-in field suppresses charge recombination and accelerates carrier migration,rationalizing the markedly enhanced PHE activity.This study offers a novel strategy for designing S-scheme heterojunctions with high light harvesting and charge utilization toward sustainable solar-tohydrogen conversion.
基金the staff of beamline BL13SSW at Shanghai Synchrotron Radiation Facility for experiments supports. This study was financially supported by the National Natural Science Foundation of China (No. 12205165)Hebei Province Innovation Ability Improvement Plan Project (No. 225676111H).
文摘Structural engineering of Pt-based nanoalloys is crucial for the rational design and manufacturing of high-performance and low-cost electrocatalysts for hydrogen evolution reaction(HER).Here,we reported PtNi nanoparticles with a refined size of 2.71 nm and regular strains loaded on carbon black,synthesized using the high-temperature liquid shock(HTLS)method.This approach offers significant advantages over conventional synthesis methods,including high scalability,rapid reaction rates,and precise control over the size and shape of nanocrystals.Importantly,the synthesized PtNi electrocatalysts demonstrate outstanding catalytic activity and long-term stability for HER,achieving low overpotentials of 19 and 203 mV at current densities of 10 and 1000 mA/cm^(2),respectively.The superior performance can be attributed to the combination of a refined particle size,lattice strains,and synergistic effects between Pt and Ni.This rapid liquid-state synthesis demonstrated here holds great potential for scalable and industrial manufacturing of micro-/nano-catalysts.
基金supported by the National Natural Science Foundation of China(22479113,52101268)the Fundamental Research Funds for the Central Universities(buctrc202323)。
文摘Efficient alkaline hydrogen evolution reaction(HER)catalysts are critical for anion exchange membrane water electrolysis(AEMWE).However,the intrinsic scaling relationship between water dissociation and OH desorption fundamentally impedes designing catalysts requiring concurrent superior water dissociation and facile OH desorption.Here,we engineer a superhydrophilic Ru/Cr_(2)O_(3) heterostructured electrocatalyst through in situ confinement of Ru nanoparticles(5-10 nm)within a Cr_(2)O_(3) matrix.Acting as a Lewis acid,the Cr_(2)O_(3) component provides alternative sites for water dissociation,accelerating the Volmer step kinetics and downshifting the Ru d-band center via interfacial charge transfer,while simultaneously adsorbing OH-to form a surface-bound Lewis base that repels excess OH-from Ru sites,thereby suppressing hydroxyl over-adsorption.Concurrently,the superhydrophilic surface architecture promotes efficient hydrogen bubble release,thereby reducing mass transport resistance.As a result,the Ru/Cr_(2)O_(3) heterostructured electrocatalyst exhibits an ultralow overpotential of 36.7 mV at 10 mA cm^(-2) and a Tafel slope of 33.2 mV dec^(-1).Integrated into an AEMWE device,the electrode delivers500 mA cm^(-2) for 2000 h in 1.0 M KOH,underscoring its industrial viability(hydrogen production energy consumption per cubic meter(EW):3.94 kW h m^(-3);electricity-to-hydrogen energy conversion efficiency(η_(ETH)):89%@80℃).
基金financially supported by the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(23KJB610003)the Natural Science Foundation of Jiangsu Province(BK20240339)+2 种基金the Science and Technology Support Plan for Youth Innovation of Colleges and Universities of Shandong Province of China(No.2023KJ104)the National Natural Science Foundation of China(No.52202092)the Natural Science Foundation of Shandong Province(No.ZR2022QE076)。
文摘Regulating the critical process of proton migration from water dissociation for boosting alkaline hydrogen evolution reaction(HER)remains a challenge.Herein,we propose an electrostatic attraction strategy to achieve the migration of a highly efficient hydrogen species to Pt sites over Pt/Co@NC,which is obtained through a facile calcination and electrodeposition method.It exhibits an outstanding geometric activity(η_(10)=31 m V),which surpasses the commercial 20 wt%Pt/C(η_(10)=37 mV).Moreover,the mass activity of Pt/Co@NC is 5.6 A mg_(Pt)^(-1) at-50 mV vs.RHE,which is 2.23 times higher than that of 20 wt%Pt/C.Experimental and theoretical results indicate that the work function of the outer carbon layer,which is changed by the introduction of the inner cobalt core,plays a crucial role in reversing the direction of electron migration between the carbon layer and Pt.The negatively charged Pt^(δ-)can spontaneously attract positively charged protons via the electrostatic interaction effect,thereby achieving the directional migration of hydrogen species.This work presents a strategy for designing advanced alkaline HER electrocatalysts by the electrostatic effect.
基金supported by the National Natural Science Foundation of China(Nos.22209088,22472082,and 22075159)Taishan Scholar Program(Nos.tsqn202103058 and tsqn202306173)Qingdao New Energy Shandong Laboratory Open Project(QNESLOP202302)。
文摘Regulating the microenvironment of the support enables precise control of electronic metal-support interactions(EMSI),boosting better catalytic activity of the metal species.However,the fundamental relationship between support defect-induced EMSI modulation and the resulting catalytic performance enhancement still needs further elucidation.Herein,a nonequilibrium high-temperature shock(HTS)method,which combines rapid high-temperature heating at 1273 K for 30 s with liquid nitrogen quenching,was adopted to load uniform Pt nanoparticles onto the nitrogen vacancy-rich TiN support(Pt@TiNVN).The catalyst demonstrates a high mass activity of 15.99 A mgPt^(-1)at an overpotential of 100 mV for the hydrogen evolution reaction(HER)in acidic solution and exhibits long-term stability for 60 h at 200 mA cm^(-2).Detailed spectroscopic characterizations and theoretical calculations reveal that the generated nitrogen vacancies can effectively modulate the charge transfer between Pt nanoparticles and the TiN-VN support,leading to a downshifted d-band center of metallic Pt and optimized Pt-H bond strength.This nonequilibrium HTS approach offers new and valuable insights into designing advanced electrocatalysts by harnessing substrate defects to modulate the electronic states of loaded noble metals.
基金support from the National Natural Science Foundation of China(No.22175060).
文摘The hydrogen evolution reaction(HER)is crucial for hydrogen production and sustainable energy storage.Molybdenum disulfide(MoS_(2)),a representative transition metal dichalcogenides(TMDs),shows potential as an HER catalyst but suffers from limited performance due to poor charge transfer and interfacial effects.Here,we report a salt-assisted chemical vapor deposition(CVD)method for synthesizing high-quality tungsten ditelluride(WTe_(2))with tunable morphologies using alkali halides(NaCl,KCl and LiCl).The prepared WTe_(2) nanoribbons and hexagonal nanosheets exhibit morphology-dependent electrical conductivity,with nanosheets showing superior performance.To evaluate WTe_(2) as a contact electrode,WTe_(2)−MoS_(2) heterostructures were fabricated and compared with graphene-MoS_(2) counterparts.The WTe_(2)−MoS_(2) heterostructure exhibits a superior Tafel slope of 111.57 mV/dec and an overpotential of 298 mV at-10 mA/cm^(2),significantly outperforming graphene-based electrodes.This improvement is attributed to the excellent conductivity of WTe_(2) and reduced interfacial Schottky barriers.Moreover,we systematically investigate the influence of WTe_(2) thickness on HER performance and assess the electrochemical durability and structural stability of the heterostructure,further confirming the effectiveness of WTe_(2) as a contact electrode for enhancing the HER activity of MoS_(2).This study offers a novel approach for enhancing the HER performance of MoS_(2) through controlled WTe_(2) growth and application as a contact electrode.Our findings provide valuable insights into the synthesis of high-quality WTe_(2) and broaden the potential applications of two-dimensional materials in energy catalysis.
基金financial support of the National Natural Science Foundation of China(NSFC)(52394202,52021004,52301232,and 52476056)the Natural Science Foundation of Chongqing Province(2024NSCQ-MSX1109).
文摘The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative solution in a pure acidic system,but the catalyst layer in direct contact with the hydrated proton environment usually leads to H_(2)evolution dominating.Herein,we show that polydimethyldiallyl-ammonium-chloride-coated Ag(Ag@PDDA)electrode exhibits outstanding performance with a FE of 86%,a single-pass conversion of 72%,and a stability of 28 h for CO production in pure-acid MEA compared with ammonium poly(N-methyl-piperidine-co-pterphenyl)decorated Ag(Ag/QAPPT)and cetyltrimethylammonium bromide decorated Ag(Ag/CTAB).The in situ ATR-SEIRAS reveal that PDDA creates a positive charge-rich protective outer layer and an N-rich hybrid inner layer,which not only suppresses the migration of H+during the electrolysis process and blocks the direct contact between H2O and Ag catalyst,but also promotes the generation from CO_(2)to*COOH in a pure-acid system.This work highlights the importance of polyelectrolyte engineering in regulating the electrocatalytic interface and accelerates the development of proton exchange membrane CO_(2)electrolysis.
基金the support from the National Key Research and Development Program of China(2023YFB4005000)the Joint Fund of Liaoning Binhai Laboratory(LBLF-2023-04)+3 种基金Dalian Science and Technology Talent Innovation Support Plan(2022RY09)Innovation Research Fund of Dalian Institute of Chemical Physics(DICP I202318)National Natural Science Foundation of China(22478384)the UK EPSRC(EP/W03784X/1)。
文摘Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent metal hydroxides deposition and boost the hydrogen evolution reaction by adding a chelating agent,EDTA-Na_(4),that chelates with Mg^(2+)/Ca^(2+),thus inhibiting their deposition and gathering them near the cathode surface,resulting in breaking the ordered hydrogen bond networks of interfacial water and reducing the activation energy of water dissociation.Furthermore,hydrolysis of–COO^(-) also promoted water dissociation to produce more active*H and*OH near the electrode surface that in turn serves as a diffusion medium for*OH,accelerating mass transfer and enabling seawater electrolysis to exhibit a stable performance,which operates continuously at 100 mA cm^(-2)@2.20 V and 200 mA cm^(-2)@2.58 V for 400 h in the symmetric electrolyzer and 500 mA cm^(-2)@2.29 V for over 500 h in the asymmetric electrolyzer.This study provides a new perspective to address the issues of stable and scalable direct seawater electrolysis for practical green hydrogen production.
基金financially supported by the National Oversea Postdoctoral Talent Attraction Programthe Pilot Group Program of the Research Fund for International Senior Scientists(52350710795)+2 种基金the Youth Fund of the National Natural Science Foundation of China(52402288)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(YESS20230183)the Yangfan Special Program of Shanghai Star Project(24YF2729700)。
文摘Defect engineering serves as a cornerstone in the design of high-effciency single-atom catalysts(SACs)for advanced electrocatalytic systems.This study demonstrates oxygen vacancy-induced near-zero-valent Pt SACs anchored on TiO2 for efficient hydrogen evolution reaction(HER).Synchrotron spectroscopy and density functional theory calculation reveal that oxygen vacancies create unconventional Pt-Ti coordination while strengthening electronic metal-support interactions.This facilitates substantial electron transfer from TiO2 to Pt,generating a near-zero-valent Pt state with elevated electron density.The modified electronic structure lowers the Pt d-band center,reducing hydrogen intermediate(*H)adsorption energy and optimizing HER kinetics.Moreover,ab initio molecular dynamics and in situ Raman spectra show that the negative charge accumulated at the Pt site promotes K^(+)enrichment at the interface,which enhances H-OH bond polarization and accelerates water dissociation kinetics.The resulting D-TiO_(2)/Pt SACs exhibit superior HER activity across acidic,neutral,and alkaline conditions,achieving low overpotentials of 40,57,and 60 mV at 10 mA cm^(-2),respectively.Additionally,its mass activities at the overpotential of 100 mV are 10.3,33.9,and 20.9 times higher that of Pt/C,respectively.This study shows the key role of defectmediated electronic engineering in tailoring SACs'valence states and catalytic functions,advancing sustainable hydrogen production through rational catalyst design.
基金supported by the Development Project of Youth Innovation Team in Shandong Colleges and Universities(No.2019KJC031)the Natural Science Foundation of Shandong Province(Nos.ZR2019MB064,ZR2021MB122 and ZR2022MB137)the Doctoral Program of Liaocheng University(No.318051608).
文摘Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction(HER)of water splitting;the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy.Ru has aroused significant concern because of its Pt-like activity and much lower price.However,it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance.
基金financially supported by the National Natural Science Foundation of China(No.5217042069)the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(CAST)(No.YESS20200103)the Fundamental Research Funds for the Central Universities(No.265QZ2022004)。
文摘Pt-based nanocatalysts offer excellent prospects for various industries.However,the low loading of Pt with excellent performance for efficient and stable nanocatalysts still presents a considerable challenge.In this study,nanocatalysts with ultralow Pt content,excellent performance,and carbon black as support were prepared through in-situ synthesis.These~2-nm particles uniformly and stably dispersed on carbon black because of the strong s-p-d orbital hybridizations between carbon black and Pt,which suppressed the agglomeration of Pt ions.This unique structure is beneficial for the hydrogen evolution reaction.The catalysts exhibited remarkable catalytic activity for hydrogen evolution reaction,exhibiting a potential of 100 mV at 100 mA·cm^(-2),which is comparable to those of commercial Pt/C catalysts.Mass activity(1.61 A/mg)was four times that of a commercial Pt/C catalyst(0.37 A/mg).The ultralow Pt loading(6.84wt%)paves the way for the development of next-generation electrocatalysts.
基金financially supported by the project of the National Natural Science Foundation of China(52322203)the Key Research and Development Program of Shaanxi Province(2024GHZDXM-21)。
文摘The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds.
基金financial support by the National Natural Science Foundation of China(No.52102241)Doctor of Suzhou University Scientific Research Foundation(Nos.2022BSK019,2020BS015)+2 种基金the Primary Research and Development Program of Anhui Province(No.201904a05020087)the Natural Science Research Project in Universities of Anhui Province in China(Nos.2022AH051386,KJ2021A1114)the Foundation(No.GZKF202211)of State Key Laboratory of Biobased Material and Green Papermaking Qilu University of Technology。
文摘Available online Alkaline water electrolysis(AWE)is a prominent technique for obtaining a sustainable hydrogen source and effectively managing the energy infrastructure.Noble metal-based electrocatalysts,owing to their exceptional hydrogen binding energy,exhibit remarkable catalytic activity and long-term stability in the hydrogen evolution reaction(HER).However,the restricted accessibility and exorbitant cost of noble-metal materials pose obstacles to their extensive adoption in industrial contexts.This review investigates strategies aimed at reducing the dependence on noble-metal electrocatalysts and developing a cost-effective alkaline HER catalyst,while considering the principles of sustainable development.The initial discussion covers the fundamental principle of HER,followed by an overview of prevalent techniques for synthesizing catalysts based on noble metals,along with a thorough examination of recent advancements.The subsequent discussion focuses on the strategies employed to improve noble metalbased catalysts,including enhancing the intrinsic activity at active sites and increasing the quantity of active sites.Ultimately,this investigation concludes by examining the present state and future direction of research in the field of electrocatalysis for the HER.
文摘Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transformation.Herein,we demonstrate that PtFeNiCoCu high-entropy alloy(HEA)nanocrystals can act as efficient cocatalysts for H_(2)evolution coupled with selective oxidation of cinnamyl alcohol to cinnamaldehyde by cubic cadmium sulfide(CdS)quantum dots(QDs)with uniform sizes of 4.0±0.5 nm.HEA nanocrystals were prepared via a simple solvothermal approach,and were successfully integrated with CdS QDs by an electrostatic self-assembly method to construct HEA/CdS composites.The optimized HEA/CdS sample presented an enhanced photocatalytic H_(2)production rate of 7.15 mmol g^(-1)h^(-1),which was 13 times that of pure CdS QDs.Moreover,a cinnamyl alcohol conversion of 96.2%with cinnamaldehyde selectivity of 99.5%was achieved after photoreaction for 3 h.The integration of HEA with CdS QDs extended the optical absorption edge from 475 to 484 nm.From d-band center analysis,Pt atoms in the HEA are the active sites for H_(2)evolution,exhibiting higher catalytic activity than pure Pt.Meanwhile,the band structure of the CdS QDs enables the oxidative transformation of cinnamyl alcohol to cinnamaldehyde with high selectivity.Moreover,femtosecond transient absorption spectroscopy shows that HEA can significantly promote the separation of photogenerated carriers in CdS,which is vital for achieving enhanced photocatalytic activity.This work inspires atomic-level design of photocatalytic materials for coordinated production of green energy carriers and value-added products.
基金the National Key Research and Development Program of China(No.2022YFB4102000)the National Natural Science Foundation of China(NSFC,Nos.22102018 and 52171201)+4 种基金the Huzhou Science and Technology Bureau(No.2022GZ45)the Hefei National Research Center for Physical Sciences at the Microscale(No.KF2021005)the China Postdoctoral Science Foundation-Funded Project(No.2022M710601)the Huzhou Science and Technology Bureau(No.2023GZ02)the Natural Science Foundation of Sichuan Province(No.24NSFSC5779)。
文摘As hydrogen energy technologies gain momentum,the role of renewable energy in facilitating sustainable hydrogen production is becoming increasingly critical.As a hydrogen production method,water electrolysis has attracted much attention from researchers due to its operational simplicity,the high purity of the hydrogen generated,and its potential for achieving zero carbon emissions throughout the process.Numerous studies has been manipulated on platinum(Pt)-based catalysts,which exhibit superior performance in hydrogen evolution reactions.Within this category,Pt nanoclusters stand out due to their unique attributes,such as quantum size effects and unique coordination environments.These features enable them to outperform both Pt metal atoms and nanoparticles in hydrogen evolution reactions regarding activity and stability.Here,we primarily delve into the reaction mechanisms underlying Pt nanocluster-based hydrogen catalysts,with particular emphasis on the interactions between the metal catalysts and their associated support materials.We provide an exhaustive summary of the strategies employed in the synthesis,the structural analyses conducted,and the performance metrics observed for Pt nanocluster catalysts when paired with various supporting materials.In closing,we explore the future potential and challenges facing Pt nanocluster-based catalysts in the context of industrial water electrolysis,along with emerging avenues for their design and optimization.
基金supported by Research Grants of the NRF(2023R1A2C2003823,RS-2024-00405818)funded by the National Research Foundation under the Ministry of Science,ICT&Future,Korea。
文摘Employing multiple metals for synergistic electronic structure regulation emerges as a promising approach to develop highly efficient and robust electrocatalysts for hydrogen evolution at ampere levels.In this study,a series of Schreibersite-type intermetallic compounds,particularly Mo_(2)Fe_(0.8)Ru_(0.2)P,are synthesized through high-temperature solid-phase synthesis.Experimental results demonstrate that the integration of Ru significantly improves the kinetics of proton adsorption and desorption during the hydrogen evolution reaction(HER).Additionally,density functional theory(DFT)calculations and X-ray absorption near edge structure(XANES)analyses effectively corroborate the pronounced d-orbital hybridization of Fe within the structure,which facilitates the transfer of hydroxide ions and the maintenance of material durability during alkaline HER processes.Remarkably,Mo_(2)Fe_(0.8)Ru_(0.2)P exhibits superior alkaline HER activity,characterized by an overpotential of merely 48 mV at a current density of 10 mA cm^(-2).After prolonged operation of 1000 h at high current densities(1.1 A cm^(-2)),the activity decline remains minimal,under 4%(with overpotential increasing from 258 mV to 268 mV).These results demonstrate the potential of strategically combining metallic elements to design high-performance industrial-grade electrocatalysts.
基金the German Research Foundation (DFG) under Germany's excellence strategy–EXC 2089/1–390776260, Germany's excellence cluster “e-conversion”the DFG project BA 5795/6-1+2 种基金funding from the European Union's Horizon 2020 research and innovation program under grant agreement HERMES No 952184the National Science Foundation (NSF) support through the NSF CAREER award (Grant No. CBET1941204)financial support from TUM Innovation Network for Artificial Intelligence powered Multifunctional Material Design (ARTEMIS).
文摘The effects of seemingly inert alkali metal(AM)cations on the electrocatalytic activity of electrode materials towards reactions essential for energy provision have become the emphasis of substantial research efforts in recent years.The hydrogen and oxygen evolution reactions during alkaline water electrolysis and the oxygen electro-reduction taking place in fuel cells are of particular importance.There is no universal theory explaining all the details of the AM cation effect in electrocatalysis.For example,it remains unclear how“spectator”AM-cations can change the kinetics of electrocatalytic reactions often more significantly than the modifications of the elec-trode structure and composition.This situation originates partly from a lack of systematic experimental and theoretical studies of this phenomenon.The present work exploits impedance spectroscopy to investigate the influence of the AM cations on the mechanism of the hydrogen evolution reaction at Pt microelectrodes.The activity follows the trend:Li^(+)≥Na^(+)≥K^(+)≥Cs^(+),where the highest activity corresponds to 0.1 M LiOH electrolytes at low overpotentials.We demonstrate that the nature of the AM cations also changes the relative contribution of the Volmer–Heyrovsky and Volmer–Tafel mechanisms to the overall reaction,with the former being more important for LiOH electrolytes.Our density functional theory-based thermodynamics and molecular dynamics calculations support these findings.
基金supported by the National Natural Science Foundation of China(No.52102470)。
文摘As a clean energy source,hydrogen plays a critical role in the global mission to achieve carbon neutrality.Among varied hydrogen production techniques,water electrolysis driven by clean energy,such as solar or wind energy,is the most promising and viable option,with the advantages of celerity,high efficiency,cleanliness,and sustainability.However,this process necessitates a highly active and durable hydrogen evolution reaction(HER)catalyst to enhance the overall reaction efficiency.This article thoroughly reviews the recent development of electrocatalysts exhibiting high-performance HER.In particular,a comprehensive look at noble metals platinum(Pt),ruthenium(Ru),iridium(Ir),and non-noble metals,including sulfides,carbides,nitrides and phosphides is taken.Synthesis strategies,methods for enhancing performance,and the correlation between structure,composition,and catalytic performance are discussed.We also pay particular attention to density functional theory(DFT)calculations to reveal the mechanisms behind the improvement of HER performance.Finally,the critical challenges associated with electrochemical water splitting and propose coping strategies are presented.
基金the final support of ARC DP220103045the startup support of KFUPMPrince Sultan University for their support。
文摘Transition metal carbides,known as MXenes,particularly Ti_(3)C_(2)T_(x),have been extensively explored as promising materials for electrochemical reactions.However,transition metal carbonitride MXenes with high nitrogen content for electrochemical reactions are rarely reported.In this work,transition metal carbonitride MXenes incorporated with Pt-based electrocatalysts,ranging from single atoms to sub-nanometer dimensions,are explored for hydrogen evolution reaction(HER).The fabricated Pt clusters/MXene catalyst exhibits superior HER performance compared to the single-atom-incorporated MXene and commercial Pt/C catalyst in both acidic and alkaline electrolytes.The optimized sample shows low overpotentials of 28,65,and 154 mV at a current densities of 10,100,and 500 m A cm^(-2),a small Tafel slope of 29 m V dec^(-1),a high mass activity of 1203 mA mgPt^(-1)and an excellent turnover frequency of 6.1 s^(-1)in the acidic electrolyte.Density functional theory calculations indicate that this high performance can be attributed to the enhanced active sites,increased surface functional groups,faster charge transfer dynamics,and stronger electronic interaction between Pt and MXene,resulting in optimized hydrogen absorption/desorption toward better HER.This work demonstrates that MXenes with a high content of nitrogen may be promising candidates for various catalytic reactions by incorporating single atoms or clusters.
文摘The issues of fossil energy shortage and environmental pollution caused by the excessive consumption of conventional fossil fuels necessitates the exploration of renewable and clean energy sources such as hydrogen,which is viable alternative to traditional energy sources in view of its high energy density and nonpolluting nature.In this regard,photocatalytic technology powered by inexhaustible solar energy is an ideal hydrogen production method.The recently developed copper-and zinc-based multinary metal sulfide(MMS)semiconductor photocatalysts exhibit the advantages of suitable bandgap,wide light-harvesting range,and flexible elemental composition,thus possessing great potential for achieving considerable photocatalytic hydrogen evolution(PHE)performance.Despite great progress has been achieved,the current photocatalysts still cannot meet the commercial application demands,which highlights the mechanisms understanding and optimization strategies for efficient PHE.Herein,the basic mechanisms of PHE,and effective optimization strategies are firstly introduced.Afterwards,the research process and the performance of copper-and zinc-based MMS photocatalysts,are thoroughly reviewed.Finally,the unresolved issues,and challenges hindering the achievement of overall water splitting have been discussed.
