Novel high entropy alloy (AgAlCuNiTi) hybridized MoS2/Si nanowires heterostructure with plasmonic enhanced photocatalytic activity

Abstract

Hydrogen has garnered widespread attention as a pivotal indicator for future sustainable development. Current research aims to utilize clean energy for hydrogen production, thereby minimizing the generation of by-products such as hydrocarbons. Two-dimensional molybdenum disulfide (2D-MoS2) has demonstrated outstanding photoelectrocatalytic (PEC) performance and shows promise as a material for photocatalytic (PC) hydrogen evolution (HER). However, its atomic-scale thickness limits light absorption. Therefore, the introduction of plasmonic metal nanoparticles to enhance light-matter interactions through the plasmonic resonance effect can substantially improve the overall catalytic efficiency. Conventional single-element noble metal nanoparticles exhibit relatively poor catalytic effects, while multi-element alloys have emerged as excellent catalysts due to their high entropy effect. In this study, we designed a heterostructure (SiNW/MoS2/HEANP) by combining silicon nanowires, molybdenum disulfide, and a novel high-entropy alloy nanoparticle to demonstrate outstanding photocatalytic hydrogen evolution performance. The silicon nanowire structure, exploiting light-trapping effects, exhibited high anti-reflection properties, achieving over 97% absorption of visible light and providing abundant reaction sites. Moreover, the mixed-phase structure of 1T and 2H MoS2, synthesized via thermal pyrolysis, contributed to the enhanced HER performance of the material. The HEA(AgAlCuNiTi) nanoparticles, synthesized through sputtering and annealing, exhibited a significant synergistic effect with MoS2 through its decent plasmonic resonance and excellent HER activity, resulting in a substantially improved overall catalytic efficiency. The SiNW/MoS2/HEANP heterostructure demonstrated a remarkable hydrogen generation rate of 475.5 mmol g-1 h-1. This study presents a strategy for utilizing HEAs as promising materials for photocatalytic hydrogen evolution with tremendous potential.