In order to improve the electrochemical kinetic performances of La-Mg-Ni-based alloy,complex surface modification of Ni with excellent catalytic activity and conducting polymer polypyrrole(PPy)was performed via electr...In order to improve the electrochemical kinetic performances of La-Mg-Ni-based alloy,complex surface modification of Ni with excellent catalytic activity and conducting polymer polypyrrole(PPy)was performed via electroless plating method.FESEM images revealed that the complex Ni-PPy treatment resulted in more micropores at the alloy surface,with Ni particles and cotton fiber-shape PPy microspheres attached.Both the larger surface area induced by the micropore and the higher catalytic activity and conductivity on account of the dispersed Ni particles/PPy microspheres promoted the electrode reaction,thereby increasing the discharge capacity of the modified alloy electrode.Electrochemical impedance spectroscopy(EIS)and linear polarization results showed that the Ni-PPy treatment decreased the charge-transfer resistance and increased the exchange current density greatly,far more than the single-component Ni or PPy treatment.Consequently,a notable improvement in high rate dischargeability(HRD)was observed,and at a high discharge current density of 1800 mA/g,the HRD of the modified electrode increased by 10.4%compared with that of the bare electrode.展开更多
基金Supported by the National Natural Science Foundation of China(Nos.51571173,51701175,51771164).
文摘In order to improve the electrochemical kinetic performances of La-Mg-Ni-based alloy,complex surface modification of Ni with excellent catalytic activity and conducting polymer polypyrrole(PPy)was performed via electroless plating method.FESEM images revealed that the complex Ni-PPy treatment resulted in more micropores at the alloy surface,with Ni particles and cotton fiber-shape PPy microspheres attached.Both the larger surface area induced by the micropore and the higher catalytic activity and conductivity on account of the dispersed Ni particles/PPy microspheres promoted the electrode reaction,thereby increasing the discharge capacity of the modified alloy electrode.Electrochemical impedance spectroscopy(EIS)and linear polarization results showed that the Ni-PPy treatment decreased the charge-transfer resistance and increased the exchange current density greatly,far more than the single-component Ni or PPy treatment.Consequently,a notable improvement in high rate dischargeability(HRD)was observed,and at a high discharge current density of 1800 mA/g,the HRD of the modified electrode increased by 10.4%compared with that of the bare electrode.