Heterostructuring Uniform 2D CdS on Ru/Ti₃C₂‐TiO₂ via In situ Oxidized Ru‐Loaded MXene for Boosting Photocatalytic H₂ Production

Abstract

Building heterojunctions and exposing more catalytic active sites are effective strategies to enhance the photocatalytic hydrogen evolution activity. Herein, TiO2 nanosheets are oxidized in situ on Ru‐loaded MXene as carriers and subsequently loaded with uniform 2D CdS via hydrothermal method to obtain 2D Ru/Ti3C2‐TiO2/CdS composite photocatalysts that integrate heterojunctions and cocatalysts. The formation of heterojunction between CdS and TiO2 is conducive to promoting the separation and transfer of photogenerated charges, simultaneously, Ru/Ti3C2 with the fully exposed Ru and Ti3C2 can act as effective active sites of photocatalytic hydrogen production reaction. The composite photocatalyst exhibits an improved hydrogen production rate with 5479 µmol g−1 h−1, which is 5, 3, and four times more than that of pristine CdS, CdS loaded Ti3C2‐TiO2 and CdS loaded Ru‐TiO2 respectively. The results reveal that the notable enhancement in performance can primarily be ascribed to the introduction of the TiO2/CdS heterojunction and the efficient cocatalysts of Ru/Ti3C2. Moreover, the 2D Ti3C2 with high conductivity as carriers can increase charge transfer, and its 2D structure can serve as a template for growing 2D photocatalysts with higher activity. The interface engineering with multiple interfaces can offer novel insights for the advancement of efficient hydrogen evolution reaction catalysts.