Hierarchical porous N-doped carbon-supported PtCu nanoparticles as an efficient catalyst for oxygen reduction reaction

The catalyst of PtCu bimetallic nanoparticles anchored on hierarchical porous N-doped carbon (PtCu/NHPC) is successfully fabricated through a simple pyrolysis synthesis. The high surface area (827 m(2) g(-1)) of N-doped porous carbon (NHPC) can effectively favor the high distribution of PtCu particles on carbon. The high mesopore ratio of NHPC helps to reduce mass transfer resistance. Furthermore, homogeneously distributed nitrogen in carbon can not only uniformly disperse nanoparticles but also optimize catalyst oxygen affinity, significantly improving catalytic efficiency for oxygen reduction reaction. PtCu/NHPC shows excellent electrocatalytic activity with a high half-wave potential (0.915 V vs. RHE) compared with commercial Pt/C (0.864 V) in half-cell test. In the single-cell system, PtCu/NHPC also behaves good performance, and its initial current density is 595 mA cm-2 at 0.85 V. PtCu/NHPC shows better durability (only 6.6% mass activity loss) after 10,000 potential cycles compared to JM Pt/C catalyst (30%). The research provides a simple preparation strategy for improving the oxygen reduction reaction activity and stability of fuel cell platinum-based catalysts.