Morphology and photocatalytic activity of TiO2 Aerogels

Abstract

In this paper we describe a methodology to form a data base that will allow us to investigate the correlation between the morphology of Ti?2 aerogels and their photocatalytic activity with respect to photodecomposition of a water soluble organic compound. We start with a qualitative theoretical argument in which we show that any functionality that involves optimization of different length scale should require some kind of ramified structure. For photocatalytic activity we need to optimize substrate and light absorptions with diffusion of products and reactants. We proceed to describe the techniques that we use to analyze and parametrize the morphology of the aerogels, using nitrogen adsorption and Small Angle Neutron Scattering. The photocatalytic activity is monitored through the photodecomposition of salicylic acid. We compare the adsorption and photodegradation of salicylic acid on the aerogels to many other forms of TiO2 and report that under our experimental conditions the photocatalytic activity of the aerogels is superior.