Hydrogen production via water electrolysis defines the novel energy vector for achieving a sustainable society.However,the true progress of the given technology is hindered by the sluggish and complex hydrogen evoluti...Hydrogen production via water electrolysis defines the novel energy vector for achieving a sustainable society.However,the true progress of the given technology is hindered by the sluggish and complex hydrogen evolution reaction(HER)occurring at the cathodic side of the system where overpriced and scarce Pt-based electrocatalysts are usually employed.Therefore,efficient platinum group metals(PGMs)-free electrocatalysts to carry out HER with accelerated kinetics are urgently demanded.In this scenario,molybdenum disulfide(MoS_(2))owing to efficacious structural attributes and optimum hydrogen-binding free energy(ΔG_(H*))is emerging as a reliable alternative to PGMs.However,the performance of MoS_(2)-based electrocatalysts is still far away from the benchmark performance.The HER activity of MoS_(2)can be improved by engineering the structural parameters i.e.,doping,defects inducement,modulating the electronic structure,stabilizing the 1 T phase,creating nanocomposites,and altering the morphologies using appropriate fabrication pathways.Here,we have comprehensively reviewed the majority of the scientific endeavors published in recent years to uplift the HER activity of MoS_(2)-based electrocatalysts using different methods.Advancements in the major fabrication strategies including hydrothermal synthesis methods,chemical vapor deposition,exfoliation techniques,plasma treatments,chemical methodologies,etc.to tune the structural parameters and hence their ultimate influence on the electrocatalytic activity in acidic and/or alkaline media have been thoroughly discussed.This study can provide encyclopedic insights about the fabrication routes that have been pursued to improve the HER performance of MoS_(2)-based electrocatalysts.展开更多
The oxygen evolution reaction(OER)is a critical bottleneck in the commercial evolution of anion exchange membrane water electrolyzers(AEMWEs).As a potential substitute for the scarce and expensive noble metal-based el...The oxygen evolution reaction(OER)is a critical bottleneck in the commercial evolution of anion exchange membrane water electrolyzers(AEMWEs).As a potential substitute for the scarce and expensive noble metal-based electrocatalysts typically used to improve the OER activity,here amorphous NiFe oxides with varying Ni/Fe ratios were synthesized using a simplistic and cost-effective sol–gel method.After carefully investigating the structural and morphological attributes of the derived electrocatalysts,their OER activities were analyzed by acquiring the half-cell measurements.First,the influence of the electrochemical ink formulation and additives on the activity of the electrocatalyst was studied,followed by elucidating the electrocatalyst loading to configure the working electrode on the rotating disk electrode(RDE).By comparing the activities of different synthesized NiFe oxides,it was observed that Ni_(0.75)Fe_(0.25)O delivers the peak performance with a minimum overpotential of ca.290 mV.Therefore,the aforementioned sample was utilized to configure the anode electrode for a lab-scale AEMWE,achieving 3.7 A cm^(−2) at 2 V and 80℃ while demonstrating promising stability trends.展开更多
Within the framework of the circular economy,the waste litchi’s skins were upgraded and transformed into electrocatalysts for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER).The waste litchi’s ski...Within the framework of the circular economy,the waste litchi’s skins were upgraded and transformed into electrocatalysts for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER).The waste litchi’s skins were pyrolyzed,activated,and then used as carbon support for fabricating metal–nitrogen–carbons(M–N–Cs)which belong to a promising class of platinum group metal-free electrocatalysts.The activated char was functionalized with transition metal(Fe,Ni,and Co)-phthalocyanine(Pc)in monometallic and bimetallic fashion by subjecting it to a thermal treatment at 600 and 900◦C.The samples functionalized at 900℃ showed higher performance for HER due to the formation of metal nanoparticles,whereas the samples functionalized at 600℃ showed higher performance for ORR.Particularly,sample Ni–Co 900 had an overpotential of−0.38 V for HER,while the sample Fe 600 was the most active electrocatalyst for ORR by demonstrating the onset potential of∼0.9 V(a half-wave potential of∼0.81 V)with the least production of unwanted peroxide anion.展开更多
In this work,platinum group metal-free(PGM-free)electrocatalysts were synthesized,characterized,and tested for hydrogen evolution reaction(HER).These materials were mono-,bi-and trimetallic Ni-based electrocatalysts w...In this work,platinum group metal-free(PGM-free)electrocatalysts were synthesized,characterized,and tested for hydrogen evolution reaction(HER).These materials were mono-,bi-and trimetallic Ni-based electrocatalysts with the addition of a second or a third transition metal(TM),such as iron and cobalt.TM–phthalocyanine(TMPc)was used as a metal precursor,mixed with a conductive carbon backbone and subjected to pyrolysis under controlled temperature and atmosphere conditions.Two temperatures of pyrolysis(600℃ and 900℃)were used.The effect of TM loading in the precursors,different pyrolysis temperatures on the surface chemistry and morphology,and electrocatalytic activity towards HER were evaluated.The increase of NiPc in the initial mixture is beneficial to improving the electrocatalytic activity.The addition of a second and a third metal reflects positively on the HER performance.Interestingly,the pyrolysis temperature influences both the formation and growth of the nanoparticles,and this information is supported by high-resolution transmission electron microscopy(HR-TEM)and light synchrotron X-ray absorption spectroscopy(XAS)measurements.展开更多
基金the Italian Ministry of University and Research(MUR)through the“Rita Levi Montalcini 2018”Fellowship(Grant number PGR18MAZLI)ENEA–UNIMIB PNRR agreement(Attività1.1.3 del PNRR POR H2)+1 种基金the Ministry of Science and Technology(State of Israel)and the Ministry of Foreign Affairs and International Cooperation–Directorate General for Cultural and Economic Promotion and Innovation(Italian Republic),respectively,within the bilateral project Italy-Israel(WE-CAT)the Italian ministry MUR for funding through the FISR 2019 project AMPERE(FISR2019_01294)。
文摘Hydrogen production via water electrolysis defines the novel energy vector for achieving a sustainable society.However,the true progress of the given technology is hindered by the sluggish and complex hydrogen evolution reaction(HER)occurring at the cathodic side of the system where overpriced and scarce Pt-based electrocatalysts are usually employed.Therefore,efficient platinum group metals(PGMs)-free electrocatalysts to carry out HER with accelerated kinetics are urgently demanded.In this scenario,molybdenum disulfide(MoS_(2))owing to efficacious structural attributes and optimum hydrogen-binding free energy(ΔG_(H*))is emerging as a reliable alternative to PGMs.However,the performance of MoS_(2)-based electrocatalysts is still far away from the benchmark performance.The HER activity of MoS_(2)can be improved by engineering the structural parameters i.e.,doping,defects inducement,modulating the electronic structure,stabilizing the 1 T phase,creating nanocomposites,and altering the morphologies using appropriate fabrication pathways.Here,we have comprehensively reviewed the majority of the scientific endeavors published in recent years to uplift the HER activity of MoS_(2)-based electrocatalysts using different methods.Advancements in the major fabrication strategies including hydrothermal synthesis methods,chemical vapor deposition,exfoliation techniques,plasma treatments,chemical methodologies,etc.to tune the structural parameters and hence their ultimate influence on the electrocatalytic activity in acidic and/or alkaline media have been thoroughly discussed.This study can provide encyclopedic insights about the fabrication routes that have been pursued to improve the HER performance of MoS_(2)-based electrocatalysts.
基金the Next Generation EU from the Italian Ministry of Environment and Energy Security POR H2Ad P MMES/ENEA with involvement of CNR and RSE, PNRR – Mission 2, Component 2, Investment 3.5 “Ricerca e sviluppo sull'idrogeno” under the ENEA – UNIMIB agreement (Procedure 1.1.3 PNRR POR H_2)the National Recovery and Resilience Plan (PNRR), Mission 2 “Green Revolution and Ecological Transition”, Component 2 “Renewable Energy, Hydrogen, Network and Sustainable Mobility”, Investment 3.5 “Hydrogen Research and Development”, European Union – Next Generation EU – Italian Ministry of Environment and Energy Security (MASE), project AMBITIONthe Circular and Sustainable Made in Italy Extended Partnership (MICS) funded by the European Union Next-Generation EU (Piano Nazionale di Ripresa e Resilienza (PNRR) – Mission 4, Component 2, Investment 1.3 – D.D. 1551.11-10-2022, PE00000004) for financial support
文摘The oxygen evolution reaction(OER)is a critical bottleneck in the commercial evolution of anion exchange membrane water electrolyzers(AEMWEs).As a potential substitute for the scarce and expensive noble metal-based electrocatalysts typically used to improve the OER activity,here amorphous NiFe oxides with varying Ni/Fe ratios were synthesized using a simplistic and cost-effective sol–gel method.After carefully investigating the structural and morphological attributes of the derived electrocatalysts,their OER activities were analyzed by acquiring the half-cell measurements.First,the influence of the electrochemical ink formulation and additives on the activity of the electrocatalyst was studied,followed by elucidating the electrocatalyst loading to configure the working electrode on the rotating disk electrode(RDE).By comparing the activities of different synthesized NiFe oxides,it was observed that Ni_(0.75)Fe_(0.25)O delivers the peak performance with a minimum overpotential of ca.290 mV.Therefore,the aforementioned sample was utilized to configure the anode electrode for a lab-scale AEMWE,achieving 3.7 A cm^(−2) at 2 V and 80℃ while demonstrating promising stability trends.
基金Italian Ministry of EducationUniversities and Research+2 种基金Ministero dell’Istruzione,dell’Universita e della Ricerca—MIUR,Grant/Award Number:PGR18MAZLIItalian ministry MIURAMPERE,Grant/Award Number:FISR2019_01294。
文摘Within the framework of the circular economy,the waste litchi’s skins were upgraded and transformed into electrocatalysts for oxygen reduction reaction(ORR)and hydrogen evolution reaction(HER).The waste litchi’s skins were pyrolyzed,activated,and then used as carbon support for fabricating metal–nitrogen–carbons(M–N–Cs)which belong to a promising class of platinum group metal-free electrocatalysts.The activated char was functionalized with transition metal(Fe,Ni,and Co)-phthalocyanine(Pc)in monometallic and bimetallic fashion by subjecting it to a thermal treatment at 600 and 900◦C.The samples functionalized at 900℃ showed higher performance for HER due to the formation of metal nanoparticles,whereas the samples functionalized at 600℃ showed higher performance for ORR.Particularly,sample Ni–Co 900 had an overpotential of−0.38 V for HER,while the sample Fe 600 was the most active electrocatalyst for ORR by demonstrating the onset potential of∼0.9 V(a half-wave potential of∼0.81 V)with the least production of unwanted peroxide anion.
文摘In this work,platinum group metal-free(PGM-free)electrocatalysts were synthesized,characterized,and tested for hydrogen evolution reaction(HER).These materials were mono-,bi-and trimetallic Ni-based electrocatalysts with the addition of a second or a third transition metal(TM),such as iron and cobalt.TM–phthalocyanine(TMPc)was used as a metal precursor,mixed with a conductive carbon backbone and subjected to pyrolysis under controlled temperature and atmosphere conditions.Two temperatures of pyrolysis(600℃ and 900℃)were used.The effect of TM loading in the precursors,different pyrolysis temperatures on the surface chemistry and morphology,and electrocatalytic activity towards HER were evaluated.The increase of NiPc in the initial mixture is beneficial to improving the electrocatalytic activity.The addition of a second and a third metal reflects positively on the HER performance.Interestingly,the pyrolysis temperature influences both the formation and growth of the nanoparticles,and this information is supported by high-resolution transmission electron microscopy(HR-TEM)and light synchrotron X-ray absorption spectroscopy(XAS)measurements.
