Coplanar Pt/C Nanomeshes with Ultrastable Oxygen Reduction Performance in Fuel Cells

Abstract Developing highly stable and efficient catalysts toward the oxygen reduction reaction is important for the long‐term operation in proton exchange membrane fuel cells. Reported herein is a facile synthesis of two‐dimensional coplanar Pt‐carbon nanomeshes (NMs) that are composed of highly distorted Pt networks (neck width of 2.05±0.72 nm) and carbon. X‐ray absorption fine structure spectroscopy demonstrated the metallic state of Pt in the coplanar Pt/C NMs. Fuel cell tests verified the excellent activity of the coplanar Pt/C NM catalyst with the peak power density of 1.21 W cm −2 and current density of 0.360 A cm −2 at 0.80 V in the H 2 /O 2 cell. Moreover, the coplanar Pt/C NM electrocatalysts showed superior stability against aggregation, with NM structures preserved intact for a long‐term operation of over 30 000 cycles for electrode measurement, and the working voltage loss was negligible after 120 h in the H 2 /O 2 single cell operation. Density‐functional theory analysis indicates the increased vacancy formation energy of Pt atoms for coplanar Pt/C NMs, restraining the tendency of Pt dissolution and aggregation.