The development of efficient, low-cost, for water splitting, particularly those stable, non-noble-metal electrocatalysts that can catalyze both the hydrogen evolution reaction (HER) at the cathode and oxygen evoluti...The development of efficient, low-cost, for water splitting, particularly those stable, non-noble-metal electrocatalysts that can catalyze both the hydrogen evolution reaction (HER) at the cathode and oxygen evolution reaction (OER) at the anode, is a challenge. We have developed a facile method for synthesizing CoSe2 nanoparticles uniformly anchored on carbon fiber paper (CoSe2/CF) via pyrolysis and selenization of in situ grown zeolitic imidazolate framework-67 (ZIF-67). CoSe2/CF shows high and stable catalytic activity in both the HER and OER in alkaline solution. At a low cell potential, i.e., 1.63 V, a water electrolyzer equipped with two CoSe2/CF electrodes gave a water-splitting current of 10 mA.cm-2. At a current of 20 mA-cm-2, it can operate without degradation for 30 h. This study not only offers a cost-effective solution for water splitting but also provides a new strategy for developing various catalytic nanostructures by changing the metal-organic framework precursors.展开更多
The rational design of effective bifunctional electrocatalysts is of paramount importance for overall water-splitting technology in sustainable energy conversion.Herein,bimetallic oxide catalysts(RuO_(2)-Co_(3)O_(4))d...The rational design of effective bifunctional electrocatalysts is of paramount importance for overall water-splitting technology in sustainable energy conversion.Herein,bimetallic oxide catalysts(RuO_(2)-Co_(3)O_(4))derived from Ru combined MOF-derivatives(MOF=metal-organic framework)were demonstrated effective for overall water splitting in an alkaline solution,owing to the combined merits such as the two-dimensional interconnected network structure,the synergetic coupling effects and increased chemical stability.The as-prepared RuO_(2)-Co_(3)O_(4) only requires an overpotential of 260 mV for oxygen evolution and 75 mV for hydrogen evolution at 10 mA/cm^(2) in 1 M KOH solution;a low cell voltage of 1.54 V was required to reach the kinetic current density of 10 mA/cm^(2) for the water electrolysis when supporting on glass carbon electrode,and very good stability for 40 h was observed.Experimental and theoretical results demonstrated the electronic structure optimization of bimetallic RuO_(2)-Co_(3)O_(4) compared to the individual metal oxide,which promoted interface charges redistribution and the d-band center downshift,resulting in increased activity and stability for water-splitting reactions.This work provides a feasible approach for developing bimetallic oxides for application in energy-relevant electrocatalysis reactions.展开更多
The rational construction of electrocatalysts with desired features is significant but challenging for superior water splitting at high current density. Herein, amorphous Co Ni S nanosheets are synthesized on nickel f...The rational construction of electrocatalysts with desired features is significant but challenging for superior water splitting at high current density. Herein, amorphous Co Ni S nanosheets are synthesized on nickel foam(NF) through a facile structure evolution strategy and present advanced performance at high current densities in water splitting. The high catalytic activity can be attributed to the sufficient active sites exposed by the flexible amorphous configuration. Moreover, the hydrophilicity and aerophobicity of a-CoNiS/NF promote surface wettability of the self-supporting electrode and avoid the aggregation of bubbles, which expedites the diffusion of electrolyte and facilitates the mass transfer. As a result, the optimized electrode demonstrates low overpotentials of 289 and 434 m V at 500 m A/cm^(2) under alkaline conditions for hydrogen evolution reaction(HER) and oxygen evolution reaction(OER), respectively. Impressively, an electrolytic water splitting cell assembled by bifunctional a-Co Ni S/NF operates with a low cell voltage of 1.46 V@10 mA/cm^(2) and reaches 1.79 V at 500 mA/cm^(2). The strategy sheds light on a competitive platform for the reasonable design of non-precious-metal electrocatalysts under high current density.展开更多
基金The project is supported by the National Natural Science Foundation of China (Nos. 21275076 and 61328401), Jiangsu Provincial Founds for Distinguished Young Scholars (No. BK20130046), Key University Science Research Project of Jiangsu Province (No. 15KJA430006), Program for New Century Excellent Talents in University (No. NCET-13-0853), QingLan Project, Nantong Key Laboratory of New Materials Industrial Technology, SERC Grant (#102170 0142) from A'STAR Singapore, the scholarship from China Scholarships Council (No. 201508320304).
文摘The development of efficient, low-cost, for water splitting, particularly those stable, non-noble-metal electrocatalysts that can catalyze both the hydrogen evolution reaction (HER) at the cathode and oxygen evolution reaction (OER) at the anode, is a challenge. We have developed a facile method for synthesizing CoSe2 nanoparticles uniformly anchored on carbon fiber paper (CoSe2/CF) via pyrolysis and selenization of in situ grown zeolitic imidazolate framework-67 (ZIF-67). CoSe2/CF shows high and stable catalytic activity in both the HER and OER in alkaline solution. At a low cell potential, i.e., 1.63 V, a water electrolyzer equipped with two CoSe2/CF electrodes gave a water-splitting current of 10 mA.cm-2. At a current of 20 mA-cm-2, it can operate without degradation for 30 h. This study not only offers a cost-effective solution for water splitting but also provides a new strategy for developing various catalytic nanostructures by changing the metal-organic framework precursors.
基金support of the National Natural Science Foundation of China(Nos.21972124,22272148)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institution.F.F.R.would like to thank the support of National Natural Science Foundation of China(No.22302168).
文摘The rational design of effective bifunctional electrocatalysts is of paramount importance for overall water-splitting technology in sustainable energy conversion.Herein,bimetallic oxide catalysts(RuO_(2)-Co_(3)O_(4))derived from Ru combined MOF-derivatives(MOF=metal-organic framework)were demonstrated effective for overall water splitting in an alkaline solution,owing to the combined merits such as the two-dimensional interconnected network structure,the synergetic coupling effects and increased chemical stability.The as-prepared RuO_(2)-Co_(3)O_(4) only requires an overpotential of 260 mV for oxygen evolution and 75 mV for hydrogen evolution at 10 mA/cm^(2) in 1 M KOH solution;a low cell voltage of 1.54 V was required to reach the kinetic current density of 10 mA/cm^(2) for the water electrolysis when supporting on glass carbon electrode,and very good stability for 40 h was observed.Experimental and theoretical results demonstrated the electronic structure optimization of bimetallic RuO_(2)-Co_(3)O_(4) compared to the individual metal oxide,which promoted interface charges redistribution and the d-band center downshift,resulting in increased activity and stability for water-splitting reactions.This work provides a feasible approach for developing bimetallic oxides for application in energy-relevant electrocatalysis reactions.
基金supported by the National Natural Science Foundation of China (Nos. 51871119, 22101132, and 22075141)Scientific and Technological Innovation Special Fund for Carbon Peak and Carbon Neutrality of Jiangsu Province (No. BK20220039)+4 种基金Jiangsu Provincial Founds for Natural Science Foundation (No. BK20210311)China Postdoctoral Science Foundation (Nos. 2018M640481 and 2019T120426)the Natural Science Foundation of Jiangsu Province (No. BK20210311)Jiangsu Postdoctoral Research Fund (No. 2019K003)the Postgraduate Research & Practice Innovation Program of NUAA (No. xcxjh20210607)。
文摘The rational construction of electrocatalysts with desired features is significant but challenging for superior water splitting at high current density. Herein, amorphous Co Ni S nanosheets are synthesized on nickel foam(NF) through a facile structure evolution strategy and present advanced performance at high current densities in water splitting. The high catalytic activity can be attributed to the sufficient active sites exposed by the flexible amorphous configuration. Moreover, the hydrophilicity and aerophobicity of a-CoNiS/NF promote surface wettability of the self-supporting electrode and avoid the aggregation of bubbles, which expedites the diffusion of electrolyte and facilitates the mass transfer. As a result, the optimized electrode demonstrates low overpotentials of 289 and 434 m V at 500 m A/cm^(2) under alkaline conditions for hydrogen evolution reaction(HER) and oxygen evolution reaction(OER), respectively. Impressively, an electrolytic water splitting cell assembled by bifunctional a-Co Ni S/NF operates with a low cell voltage of 1.46 V@10 mA/cm^(2) and reaches 1.79 V at 500 mA/cm^(2). The strategy sheds light on a competitive platform for the reasonable design of non-precious-metal electrocatalysts under high current density.