Interconnected porous nitrogen-doped carbon framework: Recoverable template fabrication and excellent electrocatalytic performance for oxygen reduction reaction

Abstract

The development of efficient metal-free catalysts for oxygen reduction reaction (ORR) is of great importance for accelerating the commercial application of fuel cell. Here, a 3D interconnected N-doped porous carbon skeleton (PC) was prepared by one-step pyrolysis strategy with the help of recyclable NaCl. Combining the advantages of template and pyrolysis, the obtained N-PC-900 product showed a large specific surface area (470.9 m2 g−1), porous structure and high N contents (pyridinic N 30.2% and graphitic N 40.2%). The high ID1/IG value of 1.76 suggested that N-PC-900 had more defects which could be produced at 900 °C. In alkaline condition, the prepared N-PC-900 exhibited positive onset potential (0.90 V), half-wave potential (0.75 V) and high current density (5.38 mA/cm2 at 0.2 V), which was close to the 20% Pt/C. The number of transferred electrons was 3.87–3.98 at a potential of 0.055–0.9 V, meaning a 4e− pathway towards the ORR. Meanwhile, the N-PC-900 displayed better durability and methanol tolerance for ORR in both acid and alkaline conditions than 20%Pt/C. This study provided a convenient and low-cost method to prepare high-performance metal-free ORR catalysts, and the product may have great potentials in ORR catalysis.