Hierarchically organized nanostructured TiO2/Pt on microfibrous carbon paper substrate for ethanol fuel cell reaction

Titanium dioxide is emerging as new class of catalyst support for fuel cell reactions. Via pulsed laser deposition, we prepare hierarchically organized and vertically aligned TiO₂/Pt nanostructured films on microfibrous carbon paper (CP) substrate at room temperature. Microstructural analyses reveal a metal-support interaction between TiO₂ and Pt. Namely; (i) the particles size of Pt on TiO₂ is smaller than those of Pt grown onto carbon paper substrate under similar condition of synthesis and (ii) Pt metallic state is transformed to ionized Pt²⁺ and Pt⁴⁺. Compared to CP/Pt electrocatalyst, the CP/TiO₂/Pt electrocatalysts (i) oxidize ethanol at much lower potentials, (ii) display superior current peak densities of more than 2.5 times higher by voltammetry, and (iii) steady state current density during long-term stability up to 8 times greater. For portable electronic applications, the binder-free and hierarchical structures of the CP/TiO₂/Pt electrocatalyst with its planar deposition make it very attractive as anode for direct ethanol fuel cells.