Fabrication of Ir/TiO2(110) planar catalysts with tailored particle size and distribution

A simple method is described by which supported Ir nanoparticles can be fab ricated in desired uniform sizes in the range of 1.5-20.0 nm with constant interparticle distances. The nanoparticles are characterized by STM. The me thod exploits the significant differences in the diffusion rates of metal a datoms and nanocrystallites, and consists of two steps: (i) vapor depositio n of Ir metal in predetermined concentrations on titania at 300 K with a po stannealing at 1200 K, and (ii) subsequent evaporation of Ir on this surfac e at 1200 K. (C) 1999 Academic Press.