Photocatalytic water splitting represents a sustainable approach for solar-driven hydrogen (H2) production. Platinum/titanium dioxide (Pt/TiO2) systems are highly efficient, with Pt enhancing charge separation and serving as active sites for reduction reactions. In this work, Pt was photodeposited onto TiO2 under controlled conditions, aiming for a Pt loading of 1 wt %, to examine the effects of three key synthesis parameters: methanol (MeOH) concentration as a sacrificial agent, TiO2 pretreatment via calcination, and Pt precursor addition strategy (single-step vs stepwise). The resulting Pt/TiO2 catalysts were then employed for photocatalytic H2 production under ultraviolet (UV) illumination. Varying MeOH content (0, 5, and 16.7 v/v %) during deposition showed that, in the absence of MeOH, Pt loading and photocatalytic stability were poor, with rapid performance decay over time. In contrast, the presence of MeOH significantly enhanced Pt loading and photocatalytic activity. Thermal treatment of TiO2, despite lowering Pt loading (0.66 wt %), enhanced activity through improved crystallinity, Pt dispersion, and oxygen vacancy formation, as confirmed by XRD and XPS analyses. Similarly, stepwise Pt precursor addition, while yielding a slightly lower Pt loading (0.68 wt %) compared to the single-step method, produced well-dispersed Pt nanoparticles that significantly improved operational stability during photocatalytic H2 production. Moreover, compared to bare TiO2, introducing Pt slightly reduces the band gap due to Pt-induced intermediate energy states, enhancing light absorption and photocatalytic efficiency. These findings demonstrate that careful control of sacrificial agent concentration, thermal treatment, and deposition strategy are essential for optimizing Pt/TiO2 photocatalysts toward efficient and stable solar H2 production.
Chamani et al. (2026) studied this question.