Self-Supported Pt-M Mesostructured Nanospheres with Intermetallic phase as Ultrastable Oxygen Reduction Electrocatalysts

Abstract

Enhancing the activity and stability of the cathode catalyst in proton exchange membrane fuel cells (PEMFCs) is of great importance for their commercialization. In this work, selfsupported 3D mesostructured Pt-Ni bimetallic nanospheres with intermetallic phase (Meso-PtNi) were prepared by nanocasting mesoporous silica nanospheres. This synthetic method was generalized for various compositions such as Pt-Co, Pt-Fe, and PtCu. Meso-PtNi catalysts showed enhanced performance in oxygen reduction reaction (ORR) measurement due to mesostructured morphology and Pt-Ni composition. Importantly, during the acceleration degradation test (ADT), the Meso-PtNi was activated during the early stage of ADT, and retained increased ORR activity up to 50,000 potential cycling. Finally, the very high activity of Meso-PtNi was also demonstrated in single cell configuration.