Naturally Derived TiO ₂ –SiO ₂ –Activated Carbon Ternary Nanocomposite for Enhanced Photocatalytic Hydrogen Production

Photocatalytic water splitting is recognized as one of the most promising and sustainable approaches for green hydrogen production. In recent years, ternary nanocomposite materials have demonstrated remarkable potential in achieving high solar‐to‐hydrogen conversion efficiencies. In this study, TiO ₂ –SiO ₂ –activated carbon (TSAC) ternary nanocomposites were synthesized from naturally abundant minerals via an acid–base extraction followed by ball milling. The incorporation of SiO ₂ into TiO ₂ enhances diffused photon scattering due to its high light reflectance, effectively redistributing incident photons in multiple directions within the nanocomposite during photocatalysis. Meanwhile, activated carbon, serving as a cocatalyst, facilitates efficient charge separation by trapping photogenerated electrons on its conductive surface, where water reduction occurs. The optimized nanocomposite containing 7.5 wt.% activated carbon (TSAC 7.5) exhibited the highest hydrogen evolution rate of 19.8 mmol/h/g _cat , which is 14.8 times higher than that of pristine TiO ₂ . Therefore, the enhanced activity arises from the synergistic effect of SiO ₂ induced internal light reflection and the electron‐trapping ability of activated carbon. Furthermore, the prepared ternary nanocomposite demonstrated excellent stability, retaining consistent activity over five consecutive photocatalytic cycles. This work presents a sustainable, scalable, and efficient strategy for developing photocatalysts derived from natural resources for green hydrogen generation.