Layered Pd oxide on PdSn nanowires for boosting direct H 2 O 2 synthesis.

Hydrogen peroxide (H 2 O 2 ) has the wide range of applications in industry and living life. However, the development of the efficient heterogeneous catalyst in the direct H 2 O 2 synthesis (DHS) from H 2 and O 2 remains a formidable challenge because of the low H 2 O 2 producibility. Herein, we develop a two-step approach to prepare PdSn nanowire catalysts, which comprises Pd oxide layered on PdSn nanowires (Pd L /PdSn-NW). The Pd L /PdSn-NW displays superior reactivity in the DHS at zero Celcius, presenting the H 2 O 2 producibility of 528 mol kg cat -1 ·h -1 and H 2 O 2 selectivity of >95%. A layer of Pd oxide on the PdSn nanowire generates bi-coordinated Pd, leading to the different adsorption behaviors of O 2 , H 2 and H 2 O 2 on the Pd L /PdSn-NW. Furthermore, the weak adsorption of H 2 O 2 on the Pd L /PdSn-NW contributes to the low activation energy and high H 2 O 2 producibility. This surface engineering approach, depositing metal layer on metal nanowires, provides a new insight in the rational designing of efficient catalyst for DHS.