Optimizing hydrogen adsorption of Ni B cocatalyst by integrating P atom for enhanced photocatalytic H2-production activity of CdS
Haoyu Long, Ping Wang, Xuefei Wang, Feng Chen, Huogen Yu
Abstract
Developing low-cost and long-lasting nickel boride (Ni x B) for hydrogen evolution reaction is desirable to favor the present renewable energy system. However, H atom adsorption on Ni active site is weakened by the electron transfer from B to Ni atom in Ni x B, causing the inhibited hydrogen-evolution process. Herein, the metalloid P is introduced into Ni x B to regulate the electron density of Ni active site, with the aim of enhancing its H atom adsorption to boost the photocatalytic H 2 -production activity of CdS. In this regard, the Ni x PB cocatalysts with a size of 8–10 nm are loaded on reduced graphene oxide (rGO) to produce Ni x PB-rGO cocatalyst, which was well coupled with CdS to prepare the Ni x PB-rGO/CdS photocatalyst. Photocatalytic hydrogen-evolution tests suggested that the Ni x PB-rGO/CdS photocatalyst displayed the highest H 2 -evolution rate of 5.79 mmol h −1 g −1 , which is 1.8 and 9.9 times over the Ni x B-rGO/CdS and rGO/CdS photocatalysts, respectively. The above improved activity of Ni x PB-rGO/CdS photocatalyst can be attributed to the promoting hydrogen adsorption of Ni atom for efficient interfacial H 2 production via the facile introduction of P heteroatom. This work provides a feasible strategy to optimize the transition metal borides cocatalysts for the photocatalytic H 2 evolution.