Developing Earth-abundant,highly efficient,and anticorrosion electrocatalysts to boost the oxygen evolution reaction(OER),oxygen reduction reaction(ORR),and hydrogen evolution reaction(HER) for the Zn–air battery(ZAB...Developing Earth-abundant,highly efficient,and anticorrosion electrocatalysts to boost the oxygen evolution reaction(OER),oxygen reduction reaction(ORR),and hydrogen evolution reaction(HER) for the Zn–air battery(ZAB) and for overall water splitting is imperative.In this study,a novel process starting with Cu2O cubes was developed to fabricate hollow NixCo1-xSe nanocages as trifunctional electrocatalysts for the OER,ORR,and HER and a reasonable formation mechanism was proposed.The Ni0.2Co0.8Se nanocages exhibited higher OER activity than its counterparts with the low overpotential of 280 mV at 10 mA cm-2.It also outperformed the other samples in the HER test with a low overpotential of 73 mV at 10 mA cm-2.As an air–cathode of a self-assembled rechargeable ZAB,it exhibited good performance,such as an ultralong cycling lifetime of > 50 h,a high round-trip efficiency of 60.86%,and a high power density of 223.5 mW cm-2.For the application in self-made all-solid-state ZAB,it also demonstrated excellent performance with a power density of 41.03 mW cm-2 and an open-circuit voltage of 1.428 V.In addition,Ni0.2Co0.8Se nanocages had superior performance in a practical overall water splitting,in which only 1.592 V was needed to achieve a current density of 10 mA cm-2.These results show that hollow NixCo1-xSe nanocages with an optimized Ni-to-Co ratio are a promising cost-effective and high-efficiency electrocatalyst for ZABs and overall water splitting in alkaline solutions.展开更多
基金the Guangzhou Science and Technology Plan Projects(No.201804010323)the Guangdong Natural Science Funds for Distinguished Young Scholars(No.2015A030306006)+3 种基金the Guangdong Innovative and Entrepreneurial Research Team Program(No.2014ZT05N200)the Fundamental Research Funds for the Central Universities(SCUT Grant No.2018ZD022)the Project for Natural Science Foundation of Guangdong Province(No.2018A030313178)the funding support from the Natural Science Foundation of Guangdong Province(No.2015A030310176)
文摘Developing Earth-abundant,highly efficient,and anticorrosion electrocatalysts to boost the oxygen evolution reaction(OER),oxygen reduction reaction(ORR),and hydrogen evolution reaction(HER) for the Zn–air battery(ZAB) and for overall water splitting is imperative.In this study,a novel process starting with Cu2O cubes was developed to fabricate hollow NixCo1-xSe nanocages as trifunctional electrocatalysts for the OER,ORR,and HER and a reasonable formation mechanism was proposed.The Ni0.2Co0.8Se nanocages exhibited higher OER activity than its counterparts with the low overpotential of 280 mV at 10 mA cm-2.It also outperformed the other samples in the HER test with a low overpotential of 73 mV at 10 mA cm-2.As an air–cathode of a self-assembled rechargeable ZAB,it exhibited good performance,such as an ultralong cycling lifetime of > 50 h,a high round-trip efficiency of 60.86%,and a high power density of 223.5 mW cm-2.For the application in self-made all-solid-state ZAB,it also demonstrated excellent performance with a power density of 41.03 mW cm-2 and an open-circuit voltage of 1.428 V.In addition,Ni0.2Co0.8Se nanocages had superior performance in a practical overall water splitting,in which only 1.592 V was needed to achieve a current density of 10 mA cm-2.These results show that hollow NixCo1-xSe nanocages with an optimized Ni-to-Co ratio are a promising cost-effective and high-efficiency electrocatalyst for ZABs and overall water splitting in alkaline solutions.
