CuGaS₂@NH₂-MIL-125(Ti) nanocomposite: Unveiling a promising catalyst for photocatalytic hydrogen generation

The development of efficient nanocomposites represents a promising strategy for enhancing the transfer and separation of photogenerated carriers within metal-organic frameworks (MOFs) for photocatalytic H₂ generation. In this study, we report, for the first time, the successful fabrication of a novel CuGaS₂@NH₂-MIL-125(Ti) nanocomposite in a two-step synthesis, consisting of octahedral NH₂-MIL-125(Ti) metal-organic frameworks interspersed with flat hexagonal plates of CuGaS₂. The CuGaS₂@NH₂-MIL-125(Ti) nanocomposite effectively mitigates the recombination rate of photogenerated electron-hole pairs. Notably, the most active CuGaS₂@NH₂-MIL-125(Ti) composite (containing 30 wt% CuGaS₂) achieves a remarkable hydrogen generation rate of 965.07 μmol/g_cat, surpassing the performance of NH₂-MIL-125(Ti) and CuGaS₂ by approximately 83 and 144 times, respectively. Additionally, the apparent quantum efficiency for the most active material at a wavelength of 380 nm is 9.07%. This study provides valuable insights into the design of efficient I-III-VI2 compound-MOF nanocomposites for H₂ generation applications.