Synergistic heterojunction engineering and photothermal 3D confinement effect for enhanced photocatalytic overall water splitting

Abstract

Appropriate material engineering aimed at enhancing both photochemical and photothermal efficiency can lead to multimechanism collaborative integration that boosts photocatalytic performance. Herein, we present a plasmonic S-scheme heterojunction photocatalyst, WO2@C/Mn0.5Cd0.5S (WCM), which is meticulously designed to improve overall water splitting (OWS) activity through the multifaceted strategy. The S-scheme heterojunction engineering, characterized by multiple defects, significantly enhances charge transfer kinetics. Furthermore, the impressive photothermal effect of W-MOF-derived WO2@C increases the efficiency of local heat and hot electron injection, thereby accelerating the catalytic process. Additionally, the porous three-dimensional (3D) carbon skeleton confines the heat internally and minimizes thermal loss effectively. Consequently, the optimized WCM-10% demonstrates exceptional photothermal conversion efficiency (η = 66.4%) across the full spectrum and achieves remarkable OWS performance, with hydrogen and oxygen evolution rates of 234.5 and 115.0 μmol•g -1 •h -1 , respectively. This work underscores the significance of synergistic heterojunction design, plasmonic enhancement, and thermal management in facilitating solar energy conversion and it opens avenues for further advancements in hybrid photocatalyst architectures.