Ultra‐Low Pt Loaded Porous Carbon Microparticles with Controlled Channel Structure for High‐Performance Fuel Cell Catalysts

Abstract Developing a highly efficient and durable proton exchange membrane fuel cell (PEMFC) using a low amount of platinum is essential for minimizing the total cost. Herein, the development of high‐performance PEMFC catalysts is demonstrated using ultra‐low Pt loaded (1 wt%) porous carbon with controlled channel diameters ( D ch = 13–63 nm), produced from block copolymer particles. The single cell based on the catalyst with the largest D ch of 63 nm yields an initial maximum power density of 1230 mW cm −2 and high durability showing 1120 mW cm −2 after 30 000 cycles under H 2 /O 2 flow, which outperforms those of commercial Pt/C catalysts despite 1/20 Pt usage. Furthermore, the catalyst shows outstanding performance with 51 kW per gram of Pt (kW ) after 30 000 cycles in H 2 /air flow, which is the highest performance reported to date. The channel structure and large D ch of the porous particles are the keys to enhancing the power density by improving the proton and mass transport.