Pd-catalyzed hydrodehalogenation of chlorinated olefins: Theoretical insights to the reaction mechanism

Abstract Density functional theory calculations are applied to study energetics of trichloroethene (TCE) hydrodechlorination over pure Pd(1 1 1), chlorine-covered Pd(1 1 1), and Pd island supported by Au(1 1 1). Our results show that in all cases C Cl bond breakings take place more readily than C H bond formations and that TCE dechlorinates fully producing CCH precursors for the hydrogenations. The reaction pathway through radical-like species provides a possible explanation to the experimental product distributions that show a nominal amount of lesser chlorinated species in the presence of excess hydrogen. The surface chlorine resulted from the TCE decomposition weakens the binding of the …