Co-Assembly of Nanoparticles in Evaporating Aerosol Droplets: Preparation of Nanoporous Pt/TiO₂ Composite Particles

摘要

Nanoporous Pt/TiO₂ micro-particles were synthesized via an aerosol assisted co-assembly (AACA) route. Aerosol droplets were produced from a colloidal mixture of 5 nm Pt and 20 nm TiO₂ nanoparticles, which formed spherical micro-aggregates of Pt and TiO₂ with average diameter of around 1.2 μm. The resulting composite micro-particles have very open structure with pore sizes ranging from 20 to 200 nm. Pt nanoparticles were found to be well dispersed on the surface of the supporting TiO₂ particles. Electrocatalytic application of the nanoporous Pt/TiO₂ composites was examined through methanol oxidation reaction. The performance of 20 wt% Pt/TiO₂ particles was found to be comparable to that of commercial 20 wt% Pt/carbon black catalyst.