CoNiSe2 Nanostructures for Clean Energy Production

摘要

Comparative investigation of the electrochemical oxygen evolution reaction (OER) activity for clean energy production was performed by fabricating three different electrodes, namely, NiSe_(2), CoSe_(2), and CoNiSe_(2), synthesized by hydrothermal treatment. Cubic, orthorhombic, and hexagonal structures of NiSe_(2), CoSe_(2), and CoNiSe_(2) were confirmed by X-ray diffraction (XRD) and also by other characterization studies. Perfect nanospheres, combination of distorted nanospheres and tiny nanoparticles, and sharp-edge nanostructures of NiSe_(2), CoSe_(2), and CoNiSe_(2) were explored by surface morphological images. Higher OER activity of the binary CoNiSe_(2) electrode was achieved as 188 mA/g current density with a comparatively low overpotential of 234 mV along with higher conductivity and low charge transfer resistance when compared to its unary NiSe_(2) and CoSe_(2) electrodes. A low Tafel slope value of 82 mV/dec was also achieved for the same binary CoNiSe_(2) electrode in a half-cell configuration. The overall 100% retention achieved for all of the fabricated electrodes in a stability test of OER activity suggested that the excellent optimum condition was obtained during the synthesis. This could definitely be a revelation in the synthesis of novel binary combinations of affordable metal selenides for clean energy production.