The CdS/CuS heterojunction prepared by room-temperature vulcanization of Cu-BTC accelerates charge carrier transfer to achieving high-efficiency photocatalytic H2 evolution

The interfacial agglomeration in photocatalysts synthesized via high-temperature methods leads to hindered charge carrier mobility, severely limiting their photocatalytic performance. Herein, we introduced a room-temperature sulfidation strategy for the fabrication of CdS/CuS heterojunctions utilizing Cu-BTC. The optimized CdS/CuS composite demonstrated an exceptional hydrogen evolution rate of 14.07 mmol·h −1 ·g −1 , which was 7.5 times greater than that of pristine CdS. The slow release of Cu 2+ from Cu-BTC at room temperature effectively inhibited interfacial agglomeration. This was further confirmed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Furthermore, the formation of a CdS/CuS type-II heterojunction was confirmed by Mott-Schottky measurements, Tauc analysis, and valence band X-ray photoelectron spectroscopy (VB-XPS) analysis. Owing to the interfacial electronic coupling of CdS/CuS, charge carrier recombination is suppressed while carrier migration and separation are accelerated, leading to a significant enhancement in the hydrogen evolution activity. This work therefore proposes a feasible room-temperature synthesis strategy for fabricating high-quality heterojunctions, which effectively suppresses interfacial agglomeration and accelerates charge carrier transfer, resulting in enhanced photocatalytic performance.