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 5479µmol g-1 h-1, which is 5, 3, and four times more than that of pristine CdS, CdS loaded Ti3C2-TiO2and 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.
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