Photoinduced interface activation strategy for enhancing photocatalytic hydrogen production performance of plasmonic nano Bi/Ni based metal-organic framework

Abstract

Utilizing plasmonic non-noble metal nanoparticles (NPs) for photocatalytic hydrogen evolution reaction is a significant step toward green energy production. However, optimizing the interface between non-noble metal NPs and semiconducting materials in metal-semiconductor composites remains challenging owing to the inevitable surface oxide layers of non-noble metal NPs because the surface oxide layers of non-noble metal NPs can suppress the transfer of photoinduced carriers, leading to poor photocatalytic performance. Herein, we propose a photoinduced interface activation strategy to reduce the number of oxide layers based on a dynamic charge-transfer mechanism under illumination conditions, with Bi NPs and a Ni-based metal-organic framework (MOF) selected as model materials. Under light illumination, the photoinduced charges and plasmonic hot electrons heavily pooled at the interface between the Bi NPs and Ni-MOF, resulting in the reduction of the oxide layer on the surface of Bi, thus attenuating its hindering effect on charge transfer. This phenomenon led to a dynamically enhanced carrier concentration in the Bi/Ni-MOF composite, with an outstanding photocatalytic hydrogen evolution rate of 5822 µmol g⁻¹ h⁻¹ achieved with the composite. The results of this study indicate that our strategy provides a new method for optimizing plasmonic non-noble metal Bi NPs with oxide layers.