PtNi/Sb_0.11SnO₂ with high durability was synthesized by adjusting the doping amount of antimony. The prepared PtNi/Sb_0.11SnO₂ retained excellent catalytic activity and hardly reduced half-wave potential in acidic conditions after 10,000 cycles, which displayed its high durability.

Abstract

Carbon-supported Pt is currently used as catalyst for oxygen reduction reaction (ORR) in fuel cells but is handicapped by carbon corrosion at high potential. Herein, a stable PtNi/SnO₂ interface structure has been designed and achieved by a two-step solvothermal method. The robust and conductive Sb-doped SnO₂ supports provide sufficient surfaces to confine PtNi alloy. Moreover, PtNi/Sb_0.11SnO₂ presents a more strongly coupled Pt-SnO₂ interface with lattice overlap of Pt (111) and SnO₂ (110), together with enhanced electron transfer from SnO₂ to Pt. Therefore, PtNi/Sb_0.11SnO₂ exhibits a high catalytic activity for ORR with a half-wave potential of 0.860 V versus reversible hydrogen electrode (RHE) and a mass activity of 166.2 mA mg_Pt ⁻¹@0.9 V in 0.1 M HClO₄ electrolyte. Importantly, accelerated degradation testing (ADT) further identify the inhibition of support corrosion and agglomeration of Pt-based active nanoparticles in PtNi/Sb_0.11SnO₂. This work highlights the significant importance of modulating metal-support interactions for improving the catalytic activity and durability of electrocatalysts.