Enhanced selective hydrodechlorination of 1,2-dichloroethane to ethylene on Pt–Ag/TiO2 catalysts prepared by sequential photodeposition

Abstract TiO 2 supported Pt–Ag bimetallic catalysts were prepared using a sequential photodeposition method (denoted as pd -Pt–Ag/TiO 2 ). For comparison, supported bimetallic catalysts were also prepared using the conventional impregnation method (denoted as im -Pt–Ag/TiO 2 ). The catalysts were characterized by X-ray diffraction, transition electron microscopy, CO chemisorption, IR spectroscopy of CO adsorption, and X-ray photoelectron spectroscopy. Characterization results indicated that photodeposition led to site-specific deposition of metallic Ag domain on the surface of Pt particles and thus to the formation of core–shell (Pt@Ag) like bimetallic species, which effectively blocked the adjacent Pt sites. However, Pt–Ag ensemble was predominant in im -Pt–Ag/TiO 2 . Accordingly, hydrodechlorination of 1,2-dichloroethane exhibited substantially higher ethylene selectivity and catalytic stability on pd -Pt–Ag/TiO 2 than on im -Pt–Ag/TiO 2 at similar Ag loading levels. Findings from this study highlight the potential of using sequentially photodeposited core–shell like bimetallic catalysts to enhance the ethylene selectivity in hydrodechlorination of 1,2-dichloroethane.