A Multi-Technique Perspective for the Calibration of Metal Dispersion and Oxygen Chemisorption on AgTiO2 Supported Adsorbents

Abstract

Absorption studies were performed in an attempt to gain a better understanding of the discrepancies that exist between the previously reported average crystallite sizes for silver titania adsorbents using oxygen chemisorption and XPS. Oxygen chemisorption, the standard technique for determining average particle size and dispersion is predicated on strong assumptions that easily lead to a misrepresentation of surface characteristics. Accounting for the native uptake of nitrated titania surface and using a Ag/O stoichiometric ratio of 2 for the polycrystalline of the silver titania system surface gave a more accurate representation of the particle size and average crystallite sizes. An atom balance versus Intensity balance demonstrates a bimodal particle size distribution is a representation of the sample. A review is given of the present understanding of silver based adsorbents developed by the Center for Microfibrous Materials Manufacturing. A coherent picture has emerged from the synthesis of all the different studies performed.