Interface-engineered Ni/CePO4 heterostuctures for efficient electro-/photo-catalytic hydrogen evolution

Abstract

Developing suitable electrocatalyst/photocatalyst cocatalyst with electron transfer and desorption of hydrogen active sites is extremely significance for hydrogen evolution reaction (HER). Herein, we develop a series of Ni/(m)CePO4 catalyst with rich interfaces via thermal treatment at low temperature with Ni-BTC/CePO4 as precursor. The as-synthesized Ni/(m)CePO4 heterojunction possess compact heterogeneous interface, and large specific surface area by loading Ni nanosphere on CePO4 nanowire. By carefully designing method, the powerfully intimated heterointerface between Ni and CePO4 conducive to the conversion of adsorption energy toward H atoms and electron conductivity, which enhance the synergic effect for electro-/photo-catalytic HER performances. Impressively, the Ni/0.1CePO4 catalyst renders outstanding electrocatalytic HER activity with an lowest overpotential of −120 mV at −10 mA cm−2 and a optimal Tafel slope of 72 mV dec−1. The overpotential of Ni/0.1CePO4 catalyst is −288 mV at −100 mA cm−2, close to 20 wt% Pt/C. With Eosin Y as photosensitizer, the photocatalytic performance for H2 generation speed is around 64 umol h−1. Additionally, the Ni/0.1CePO4 catalyst exhibits wonderful cycle stability in both electro-/photo-catalytic HER. The possible speculation of mechanisms of HER have also been proposed. This work provides a new insight into design HER catalysts for electro-/photo-catalytic hydrogen evolution reaction.