Photocatalytic properties of redox-treated Pt/TiO2 photocatalysts for H2 production from an aqueous methanol solution

The influence of redox-treated Pt/TiO2 photocatalysts on H2 production is investigated. Catalyst characterizations are performed by TEM, XPS, XRD, BET, and UV–vis/DR spectroscopy techniques. In terms of production rate, the oxidation treatment shows higher reactivity than the reduction treatment. The reduction treatment allows the formation of metallic Pt(0), which more easily catalyzes the transition of TiO2 from the anatase to the rutile phases. Reduction-treated Pt/TiO2 photocatalysts have lower SBET values than oxidation-treated Pt/TiO2 photocatalysts due to the higher percentage of TiO2 in the rutile phase. Combining the results of XPS and optical analyses, PtO/TiO2 shows a higher energy band gap than metallic Pt(0)/TiO2, indicating that oxidation-treated Pt/TiO2 is more capable of achieving water splitting for H2 production. According to the results of this study, the oxidation treatment of Pt/TiO2 photocatalysts can significantly enhance the reactivity of photocatalytic H2 production because of their homogenous distribution, lower phase transition, higher SBET, and higher energy band gap.