In Situ X-ray Absorption Fine Structure Studies on the Effect of pH on Pt Electronic Density during Aqueous Phase Reforming of Glycerol

Abstract

In situ X-ray absorption spectroscopy (XAS) results on correlating the Pt local coordination and electronic structure with the Pt/C catalyst activity and selectivity during aqueous reforming of glycerol at different pH are reported. The results show that both low and high pH favor C–O cleavage over that of C–C. However, the selectivity toward C–O bond cleavage was higher under the acidic conditions. XANES measurements under reaction conditions showed that low pH increased the Pt electron density while the effect of basic conditions was minimal. ΔXANES was used to estimate the coverage of adsorbates under reaction conditions and the results suggest a change in the adsorbates coverage by the acidic conditions, resulting in higher electron density on Pt.