Electrochemically active novel amorphous carbon (a-C)/Cu3P peapod nanowires by low-temperature chemical vapor phosphorization reaction as high efficient electrocatalysts for hydrogen evolution reaction

Abstract

Toward finding low-cost electrocatalysts with high catalytic properties to replace noble metals as high efficient electrocatalysts in electrochemical hydrogen evolution reaction (HER) of total water splitting plays a vital role to approach the green and sustainable energy supply. Here, we demonstrate the direct growth of novel copper phosphide coated with amorphous carbon, namely heterostructured a-C/Cu3P peapod nanowires from chemically synthesized copper nanowires (Cu NWs) followed by a chemical vapor phosphorization reaction (CVPR) process at a low temperature of 400 degrees C. The heterostructured a-C/Cu3P peapod nanowires exhibit a superior electrocatalytic activity by a lower overpotential of 287 mV at a current density of 10 mA cm(-2) with a low Tafel slope of 72 mV dec(-1) and excellent stability over 1000 cycles. The superior electrocatalytic performance can be explained by the superior contact of the electrolyte with active sites on the heterostructured a-C/Cu3P due to the high surface area of peapod nanowire structure covered by defective edges of graphene with the encapsulated amorphous carbon layer, which can tremendously enhance electrical conductivity at the surface. (C) 2019 Published by Elsevier Ltd.