As the kinetically sluggish oxygen evolution reaction(OER)is considered to be a bottleneck in overall water splitting,it is necessary to develop a highly active and stable electrocatalyst to overcome this issue.Herein...As the kinetically sluggish oxygen evolution reaction(OER)is considered to be a bottleneck in overall water splitting,it is necessary to develop a highly active and stable electrocatalyst to overcome this issue.Herein,we successfully fabricated a three-dimensional iron-dysprosium oxide co-regulated in-situ formed MOF-Ni arrays on carbon cloth(FeDy@MOF-Ni/CC)through a facile two-step hydrothermal method.Electrochemical studies demonstrate that the designed FeDy@MOF-Ni/CC catalyst requires an overpotential of only 251 mV to reach 10 mA cm-2 with a small Tafel slope of 52.1 mV dec-1.Additionally,the stability declined by only 5.5%after 80 h of continuous testing in 1.0 M KOH.Furthermore,a cell voltage of only 1.57 V in the overall water splitting system is sufficient to achieve 10 mA cm-2;this value is far better than that of most previously reported catalysts.The excellent catalytic performance originates from the unique 3D rhombus-like structure,as well as coupling synergies of Fe-Dy-Ni species.The combination of lanthanide and transition metal species in the synthesis strategy may open entirely new possibilities with promising potential in the design of highly active OER electrocatalysts.展开更多
Constructing a low cost,and high-efficiency oxygen evolution reaction(OER)electrocatalyst is of great significance for improving the performance of alkaline electrolyzer,which is still suffering from highenergy consum...Constructing a low cost,and high-efficiency oxygen evolution reaction(OER)electrocatalyst is of great significance for improving the performance of alkaline electrolyzer,which is still suffering from highenergy consumption.Herein,we created a porous iron phosphide and tungsten oxide self-supporting electrocatalyst with oxygen-containing vacancies on foam nickel(Fe_(2)P-WO_(2.92)/NF)through a facile insitu growth,etching and phosphating strategies.The sequence-controllable strategy will not only generate oxygen vacancies and improve the charge transfer between Fe_(2)P and WO_(2.92) components,but also improve the catalyst porosity and expose more active sites.Electrochemical studies illustrate that the Fe_(2)P-WO_(2.92)/NF catalyst presents good OER activity with a low overpotential of 267 mV at 100 mA cm^(-2),a small Tafel slope of 46.3 mV dec^(-1),high electrical conductivity,and reliable stability at high current density(100 mA cm^(-2) for over 60 h in 1.0 M KOH solution).Most significantly,the operating cell voltage of Fe_(2)P-WO_(2.92)/NF‖Pt/C is as low as 1.90 V at 400 mA cm^(-2) in alkaline condition,which is one of the lowest reported in the literature.The electrocatalytic mechanism shows that the oxygen vacancies and the synergy between Fe_(2)P and WO_(2.92) can adjust the electronic structure and provide more reaction sites,thereby synergistically increasing OER activity.This work provides a feasible strategy to fabricate high-efficiency and stable non-noble metal OER electrocatalysts on the engineering interface.展开更多
Chiral supramolecular polyelectrolyte nanoporous membranes(CSPPMs) are increasingly important owing to their potential applications in sensing,separation technology,and bioengineering.However,developing such membranes...Chiral supramolecular polyelectrolyte nanoporous membranes(CSPPMs) are increasingly important owing to their potential applications in sensing,separation technology,and bioengineering.However,developing such membranes remains challenging due to the lack of suitable synthetic approaches.Herein,we introduce a facile and conceptual approach that uses water molecules as dynamic crosslinkers and pore-forming agents to create CSPPMs from single-component chiral poly(ionic liquid)s.The experimental and theoretical calculation results demonstrated that the supramolecular network of CSPPMs was crosslinked by hydrogen(H)-bonding,C–H···π,electrostatic,and π-π interactions.During pore architecture formation in the membranes,an intriguing chiral amplification phenomenon was observed.This phenomenon,combined with the unique fluorescence properties and high enantioselectivity of CSPPMs toward chiral vip molecules,enables easy discrimination of enantiomers under UV lamps or even with the naked eye.The knowledge gained from this fundamental study could serve as a springboard for developing multifunctional chiral polyelectrolyte membranes for diverse applications.展开更多
文摘As the kinetically sluggish oxygen evolution reaction(OER)is considered to be a bottleneck in overall water splitting,it is necessary to develop a highly active and stable electrocatalyst to overcome this issue.Herein,we successfully fabricated a three-dimensional iron-dysprosium oxide co-regulated in-situ formed MOF-Ni arrays on carbon cloth(FeDy@MOF-Ni/CC)through a facile two-step hydrothermal method.Electrochemical studies demonstrate that the designed FeDy@MOF-Ni/CC catalyst requires an overpotential of only 251 mV to reach 10 mA cm-2 with a small Tafel slope of 52.1 mV dec-1.Additionally,the stability declined by only 5.5%after 80 h of continuous testing in 1.0 M KOH.Furthermore,a cell voltage of only 1.57 V in the overall water splitting system is sufficient to achieve 10 mA cm-2;this value is far better than that of most previously reported catalysts.The excellent catalytic performance originates from the unique 3D rhombus-like structure,as well as coupling synergies of Fe-Dy-Ni species.The combination of lanthanide and transition metal species in the synthesis strategy may open entirely new possibilities with promising potential in the design of highly active OER electrocatalysts.
基金supported by the National Natural Science Foundation of China(no.21965005)the Natural Science Foundation of Guangxi Province(2018GXNSFAA294077,2021GXNSFAA076001)+1 种基金the Project of High-Level Talents of Guangxi(F-KA18015)Guangxi Technology Base and Talent Subject(GUIKE AD18126001,GUIKE AD20297039)。
文摘Constructing a low cost,and high-efficiency oxygen evolution reaction(OER)electrocatalyst is of great significance for improving the performance of alkaline electrolyzer,which is still suffering from highenergy consumption.Herein,we created a porous iron phosphide and tungsten oxide self-supporting electrocatalyst with oxygen-containing vacancies on foam nickel(Fe_(2)P-WO_(2.92)/NF)through a facile insitu growth,etching and phosphating strategies.The sequence-controllable strategy will not only generate oxygen vacancies and improve the charge transfer between Fe_(2)P and WO_(2.92) components,but also improve the catalyst porosity and expose more active sites.Electrochemical studies illustrate that the Fe_(2)P-WO_(2.92)/NF catalyst presents good OER activity with a low overpotential of 267 mV at 100 mA cm^(-2),a small Tafel slope of 46.3 mV dec^(-1),high electrical conductivity,and reliable stability at high current density(100 mA cm^(-2) for over 60 h in 1.0 M KOH solution).Most significantly,the operating cell voltage of Fe_(2)P-WO_(2.92)/NF‖Pt/C is as low as 1.90 V at 400 mA cm^(-2) in alkaline condition,which is one of the lowest reported in the literature.The electrocatalytic mechanism shows that the oxygen vacancies and the synergy between Fe_(2)P and WO_(2.92) can adjust the electronic structure and provide more reaction sites,thereby synergistically increasing OER activity.This work provides a feasible strategy to fabricate high-efficiency and stable non-noble metal OER electrocatalysts on the engineering interface.
基金supported by the National Natural Science Foundation of China (52373008)the Natural Science Foundation of Tianjin City (21JCZDJC00250)+1 种基金the National Program for Support of Top-notch Young Professionalsthe Fundamental Research Funds for the Central Universities (020-92512027)。
文摘Chiral supramolecular polyelectrolyte nanoporous membranes(CSPPMs) are increasingly important owing to their potential applications in sensing,separation technology,and bioengineering.However,developing such membranes remains challenging due to the lack of suitable synthetic approaches.Herein,we introduce a facile and conceptual approach that uses water molecules as dynamic crosslinkers and pore-forming agents to create CSPPMs from single-component chiral poly(ionic liquid)s.The experimental and theoretical calculation results demonstrated that the supramolecular network of CSPPMs was crosslinked by hydrogen(H)-bonding,C–H···π,electrostatic,and π-π interactions.During pore architecture formation in the membranes,an intriguing chiral amplification phenomenon was observed.This phenomenon,combined with the unique fluorescence properties and high enantioselectivity of CSPPMs toward chiral vip molecules,enables easy discrimination of enantiomers under UV lamps or even with the naked eye.The knowledge gained from this fundamental study could serve as a springboard for developing multifunctional chiral polyelectrolyte membranes for diverse applications.
