Layered Pd oxide on PdSn nanowires for boosting direct H₂O₂ synthesis

Hydrogen peroxide (H₂O₂) has the wide range of applications in industry and living life. However, the development of the efficient heterogeneous catalyst in the direct H₂O₂ synthesis (DHS) from H₂ and O₂ remains a formidable challenge because of the low H₂O₂ 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 H₂O₂ producibility of 528 mol kg_cat^-1·h^-1 and H₂O₂ selectivity of >95%. A layer of Pd oxide on the PdSn nanowire generates bi-coordinated Pd, leading to the different adsorption behaviors of O₂, H₂ and H₂O₂ on the Pd_L/PdSn-NW. Furthermore, the weak adsorption of H₂O₂ on the Pd_L/PdSn-NW contributes to the low activation energy and high H₂O₂ producibility. This surface engineering approach, depositing metal layer on metal nanowires, provides a new insight in the rational designing of efficient catalyst for DHS.