Nanostructured Ti0.7Mo0.3O2 Support Enhances Electron Transfer to Pt: High-Performance Catalyst for Oxygen Reduction Reaction

The slow rate of the oxygen reduction reaction (ORR) and the instability of Pt-based catalysts are two of the most important issues that must be solved in order to make proton exchange membrane fuel cells (PEMFCs) a reality. Additionally, the serious carbon corrosion on the cathode side is a critical problem with respect to the durability of catalyst that limits its wide application. Here, we present a new approach by exploring robust noncarbon Ti0.7Mo0.3O2 used as a novel functionalized cocatalytic support for Pt. This approach is based on the novel nanostructure Ti0.7Mo0.3O2 support with "electronic transfer mechanism" from Ti0.7Mo0.3O2 to Pt that can modify the surface electronic structure of Pt, owing to a shift in the d-band center of the surface Pt atoms. Furthermore, another benefit of Ti0.7Mo0.3O2 is the extremely high stability of Pt/Ti0.7Mo0.3O2 during potential cycling, which is attributable to the strong metal/support interaction (SMSI) between Pt and Ti0.7Mo0.3O2. This also enhances the inherent structural and chemical stability and the corrosion resistance of the TiO2-based oxide in acidic and oxidative environments. We also demonstrate that the ORR current densities generated using cocatalytic Pt/Ti0.7Mo0.3O2 are respectively ∼7- and 2.6-fold higher than those of commercial Pt/C and PtCo/C catalysts with the same Pt loading. This new approach opens a reliable path to the discovery advanced concept in designing new catalysts that can replace the traditional catalytic structure and motivate further research in the field.