Abstract:
Photocatalytic hydrogen production through water splitting offers a green
alternative to fossil fuels. In this study, a novel binary nanocomposite,
MgIn2S4@NH2-MIL-125(Ti) (MIS@TIM), was fabricated via a
hydrothermal-assisted method to construct a direct Z-scheme
heterojunction. The integration of the visible-light-responsive MIS with the
highly porous and photoactive TIM facilitates efficient charge separation
and directional electron transfer, thereby enhancing photocatalytic
performance. Comprehensive structural, morphological, and optical
characterizations confirmed the successful formation of the heterojunction
and its favorable interfacial contact. Under visible-light irradiation, the
optimized MIS@TIM composite (30 wt% TIM) achieved a remarkable
hydrogen evolution rate of 2247 μmol g−1 h−1, representing ∼26-fold
enhancement over TIM and ∼32-fold over MIS, highlighting the synergistic
effect of the Z-scheme architecture in promoting photocatalytic efficiency.
The MIS@TIM composite showed strong photostability with sustained
hydrogen production for 16 h under visible light. Performance was
optimized through sacrificial agent, TEOA, and catalyst loading studies,
achieving an AQY of 7.5% at 420 nm and an SY of 1.72 μmolh−1cm−3.
Mechanistic analysis confirmed efficient charge transfer and active species
involvement, highlighting MIS@TIM as a promising, noble-metal-free
photocatalyst for sustainable hydrogen generation.
