Electrocatalytic production of hydrogen over highly efficient ultrathin carbon encapsulated S, P co-existence copper nanorods composite

Abstract

Electrocatalysis plays a key role in energy conversion processes (such as hydrogen evolution reaction-HER) to several renewable energy technologies developed to reduce our dependence on fossil fuels. It is of great importance to design and develop robust electrocatalysts, for hydrogen production from water electrolysis, composed exclusively of low cost, non-precious elements that exhibit activity and stability comparable to those of the noble metals. In the present work, taking into account the high conductivity of carbon, a nitrogen-doped ultrathin carbon sheath covered Cu2S–Cu3P (Cu2S–Cu3P@C) as integrated architecture is synthesized. Remarkably, Cu2S–Cu3P@C, as a novel HER cathode operating in 0.5 M H2SO4 electrolyte exhibits a low onset potential of 48 mV, an overpotential of 85 mV at −10 mA cm−2 and a small Tafel slope of 34 mV dec−1. Meanwhile, after 80 h holding at −400 mA cm−2, the decrease in activity is negligible, demonstrating an excellent stability that outperforms most of the Cu-based electrocatalysts reported recently. The performance improvement is due to a unique carbon encapsulation structure, which could enhance the conductivity, facilitate the charge transfers and improve the corrosion resistance. This study will be beneficial to design and development of high performance non-precious metal electrocatalysts applied for electrocatalytic hydrogen generation. © 2019 Elsevier Ltd