Design at the nanometre scale of multifunctional materials using supercritical fluid chemical deposition

Nanotechnology. 2006 Sep 28;17(18):4594-9. doi: 10.1088/0957-4484/17/18/011. Epub 2006 Aug 29.

Abstract

Recent developments in multifunctional devices show the interest in combining different materials to obtain specific properties. Through supercritical fluid chemical deposition (SFCD), silica spheres, used as a model support, were coated with copper nanoparticles (5-17 nm) with a tuneable amount of coverage (40-80%). The coating process is based on the reduction of metal precursors with hydrogen in a supercritical CO(2)/isopropanol mixture in a temperature range between 100 and 150 °C at 24 MPa. Several parameters were studied such as temperature, residence time or mass ratio of precursor/silica spheres, allowing control of the size of the copper nanoparticles and of the amount of coverage from metal nanoparticles scattered onto the surface to a metal nanoparticle thin film.