Maize-like CoP nanorod arrays as an efficient and robust electrocatalyst for superior hydrogen generation

High-performance, low-cost and robust electrocatalysts for the hydrogen evolution reaction (HER) play a critical role in large-scale hydrogen production via water splitting. Herein, we proposed a synthesis strategy for the self-assembly of maize-like CoP nanorod arrays with abundant active sites via a combination of conventional hydrothermal reaction and low-temperature phosphorization. This unique architecture exhibited remarkable catalytic performance for the HER, with a low overpotential of 130 mV at a current density of 10 mA cm(-2) and a small Tafel slope of 59 mV dec(-1) in 1.0 M KOH electrolyte, as well as good stability as verified by chronoamperometry measurement for 10 h. Density functional theory calculations further revealed that these maize-like CoP nanorod arrays with dense active sites and a high phosphorization degree could boost the HER performance in terms of low adsorption energy and free energy. This work provided a facile strategy towards manipulating morphology engineering to enhance the HER activity of CoP-based catalysts. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study presents a synthesis strategy for the self-assembly of maize-like CoP nanorod arrays with abundant active sites, which exhibit remarkable catalytic performance for the hydrogen evolution reaction (HER). The unique architecture with dense active sites and a high phosphorization degree boosts the HER performance in terms of low adsorption energy and free energy. This work provides a facile strategy for morphology engineering to enhance the HER activity of CoP-based catalysts.