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

Developing highly stable and efficient catalysts toward oxygen reduction reaction is of great importance for the long-term operation in proton exchange membrane fuel cells but still challenging. Herein, we report 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 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 H 2 /O 2 cell. Moreover, the coplanar Pt/C NM electrocatalysts showed superior stability against aggregation with nanomesh structures preserved intact in a long-term operation over 30,000 cycles for electrode measurement, and the working voltage loss was negligible after 120 h in 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.