Interfacial synergistic effect in SnO2/PtNi nanocrystals enclosed by high-index facets for high-efficiency ethylene glycol electrooxidation

Abstract

Strengthening the oxide—metal interfacial synergistic interaction in nanocatalysts is identified as potential strategy to boost intrinsic activities and the availability of active sites by regulating the surface/interface environment of catalysts. Herein, the SnO2/PtNi concave nanocubes (CNCs) enclosed by high-index facets (HIFs) with tunable SnO2 composition are successfully fabricated through combining the hydrothermal and self-assembly method. The interfacial interaction between ultrafine SnO2 nanoparticles and PtNi with HIFs surface structure is characterized by analytical techniques. The as-prepared 0.20%SnO2/PtNi catalyst exhibits extraordinarily high catalytic performance for ethylene glycol electrooxidation (EGOR) in acidic conditions with specific activity of 3.06 mA/cm2, which represents 6.2-fold enhancement compared with the state-of-the-art Pt/C catalyst. Additionally, the kinetic study demonstrates that the strong interfacial interaction between SnO2 and PtNi not only degrades the activation energy barrier during the process of EGOR but also enhances the CO-resistance ability and long-term stability. This study provides a novel perspective to construct highly efficient and stable electrocatalysts for energy conversions.