Platinum nanoparticles encapsulated in mesoporous silica: Preparation, characterisation and catalytic activity in toluene hydrogenation

The material was tested in toluene hydrogenation as a model reaction and the catalytic activity was compared with a conventional Pt supported on SBA-15, prepared using the incipient wetness technique. The conventional catalyst was considerably more active in the toluene hydrogenation due to a higher Pt dispersion, as measured by hydrogen chemisorption, but the turnover frequencies were comparable. There is some discrepancy between the Pt particle size as observed by TEM and the chemisorption data. This is probably caused by formation of agglomerates of Pt particles, or that the Pt active sites are blocked, e.g. by a remaining copolymer layer on the surface of the particles.