In this study,carboxylated multi-walled carbon nanotubes(CNTs)were utilized to address the challenges of inherent conductivity mismatch of CuCoO_(2)catalysts.CNT-supported CuCoO_(2)nanosheets(CCO/xCNT,x=25,50,and 75)w...In this study,carboxylated multi-walled carbon nanotubes(CNTs)were utilized to address the challenges of inherent conductivity mismatch of CuCoO_(2)catalysts.CNT-supported CuCoO_(2)nanosheets(CCO/xCNT,x=25,50,and 75)were successfully synthesized through a one-step hydrothermal method.The introduction of CNTs can reduce the thickness of CuCoO_(2)to 25 nm due to the interaction between the CNTs and CuCoO_(2),change the electronic structure,and increase the O-Co bond length and oxygen vacancy(V_(O))concentration of CuCoO_(2).These microstructure modifications significantly enhance the binding affinity between CuCoO_(2)and OH^(-).The OER measurements of CCO/xCNT(x=25,50,and 75)electrocatalysts reveal that adding 50 wt%CNTs into the sample(CCO/50CNT)yields the best catalytic performance,which shows a low overpotential of only 343 mV at 10 mA cm^(-2)and a small Tafel slope of 65 mV dec^(-1).Additionally,CCO/50CNT also exhibits excellent structural and compositional stability.The density functional theory(DFT)calculations and pH dependence experiments show that the introduction of CNTs can generate V_(O),which initiates lattice oxygen and facilitates both the Adsorption Evolution Mechanism(AEM)and the Lattice Oxygen Mechanism(LOM)on the catalyst surface during the OER process.A simple and general strategy is used to modify the catalyst microstructure and influence its OER mechanism,which helps to improve the OER performance of delafossite type metal oxides and even bimetallic oxides.展开更多
Herein,we report the low temperature hydrothermal synthesis of delafossite CuCoO_(2)crystals at 100℃.The structural,morphological and compositional characterization of CuCoO_(2)crystals was performed by powder X-ray ...Herein,we report the low temperature hydrothermal synthesis of delafossite CuCoO_(2)crystals at 100℃.The structural,morphological and compositional characterization of CuCoO_(2)crystals was performed by powder X-ray diffraction(PXRD),field-emission scanning electron microscopy(FESEM)and X-ray photoelectron spectroscopy(XPS).Furthermore,the thermal stability of CuCoO_(2)in air and its electro-catalytic activity toward the oxygen evolution reaction(OER)have also been investigated.展开更多
基金Natural Science Foundation of Hubei Province(Grant No.2023AFB085)the Fundamental Research Funds for the Central Universities(WUT:2024III012JL)the National Innovation and Entrepreneurship Training Program for College Students in Wuhan University of Technology(Grant No.S202310497028)for the financial support.
文摘In this study,carboxylated multi-walled carbon nanotubes(CNTs)were utilized to address the challenges of inherent conductivity mismatch of CuCoO_(2)catalysts.CNT-supported CuCoO_(2)nanosheets(CCO/xCNT,x=25,50,and 75)were successfully synthesized through a one-step hydrothermal method.The introduction of CNTs can reduce the thickness of CuCoO_(2)to 25 nm due to the interaction between the CNTs and CuCoO_(2),change the electronic structure,and increase the O-Co bond length and oxygen vacancy(V_(O))concentration of CuCoO_(2).These microstructure modifications significantly enhance the binding affinity between CuCoO_(2)and OH^(-).The OER measurements of CCO/xCNT(x=25,50,and 75)electrocatalysts reveal that adding 50 wt%CNTs into the sample(CCO/50CNT)yields the best catalytic performance,which shows a low overpotential of only 343 mV at 10 mA cm^(-2)and a small Tafel slope of 65 mV dec^(-1).Additionally,CCO/50CNT also exhibits excellent structural and compositional stability.The density functional theory(DFT)calculations and pH dependence experiments show that the introduction of CNTs can generate V_(O),which initiates lattice oxygen and facilitates both the Adsorption Evolution Mechanism(AEM)and the Lattice Oxygen Mechanism(LOM)on the catalyst surface during the OER process.A simple and general strategy is used to modify the catalyst microstructure and influence its OER mechanism,which helps to improve the OER performance of delafossite type metal oxides and even bimetallic oxides.
基金support by the National Natural Science Foundation of China(No.51402223,51772224).
文摘Herein,we report the low temperature hydrothermal synthesis of delafossite CuCoO_(2)crystals at 100℃.The structural,morphological and compositional characterization of CuCoO_(2)crystals was performed by powder X-ray diffraction(PXRD),field-emission scanning electron microscopy(FESEM)and X-ray photoelectron spectroscopy(XPS).Furthermore,the thermal stability of CuCoO_(2)in air and its electro-catalytic activity toward the oxygen evolution reaction(OER)have also been investigated.
