Releasing the limited catalytic activity of CeO2-supported noble metal catalysts via UV-induced deep dechlorination.

[Display omitted] • A facile photochemical synthetic strategy to support noble metal single atoms onto CeO 2 is developed. • An efficient dechlorination strategy, where the stubborn Cl ions strongly binding to Pt sites are deeply removed from the catalyst, is proposed via photo-deposition. • Surface oxygen on CeO 2 is activated after dechlorination, resulting in enhanced capability of H 2 O dissociation. • The water–gas shift activity is thus promoted. Such strategy shows universality toward different metals, supports and reactions. During regular synthesis, the supported catalysts may suffer from incomplete exposure of metal sites, whose activity may accordingly be limited by the stubborn residues and inert coordination environment. Here we report a photochemical strategy to fabricate promoted Pt-CeO 2 catalysts, where UV-induced deep dechlorination and the following surface oxygen activation are achieved. With a photo-deposition method, the usually neglected stubborn Cl residues are easily removed from Pt-CeO 2. The adjacent oxygen species are activated under UV illumination, whose flexible elimination creates sufficient surface vacancies, resulting in enhanced H 2 O dissociation. The derived catalyst shows excellent performances for the water–gas shift (WGS) reaction. Such strategy shows universality toward different metals, supports and reactions. This work sheds light on the synthesis of robust catalysts, by applying photochemical method for Cl removal and surface oxygen activation. The universal strategy shows great potentials in developing promoted solid catalysts for various heterogeneous reactions. [ABSTRACT FROM AUTHOR]