Robust non-carbon Ti0.7Ru0.3O2 support with co-catalytic functionality for Pt: enhances catalytic activity and durability for fuel cells

Abstract

Multifunctional binary metal oxide (Ti_0.7Ru_0.3O₂), a novel functionalised co-catalytic support for Pt, is synthesized in a simple one-step hydrothermal process at low temperature. In practical applications Ti_0.7Ru_0.3O₂ offers both excellent improvements in electrocatalytic activity and durability over commercial carbon supported Pt and PtRu catalysts for direct methanol fuel cell (DMFC), while at the molecular level it provides advantages in terms of its high surface area, and the strong interactions between Pt and the co-catalytic support. The Ti_0.7Ru_0.3O₂ support acts as a co-catalyst supporting Pt activity, due to the high proton conductivity of hydrated Ti_0.7Ru_0.3O₂ which underlies a ‘bifunctional mechanism’ and the synergistic effect between Pt and Ti_0.7Ru_0.3O₂, modifying the electronic nature of the metal particles as well, which additionally enhances CO-tolerance, the catalytic activity and durability for methanol and hydrogen oxidation. Additionally, Ti_0.7Ru_0.3O₂ can be fabricated as a much thinner catalyst layer resulting in improving mass transport kinetics, giving a broad scope for its wider application in other fuel cells, as demonstrated here by its application in a direct methanol fuel cell (DMFC) and polymer electrolyte membrane fuel cell (PEMFC) and can also be extended to other areas such as catalytic biosensor technology.