B, N‐codoped Cu–N/B–C Composite as an Efficient Electrocatalyst for Oxygen‐Reduction Reaction in Alkaline Media
Li–Mei Liao, Ye‐Min Zhao, Chao Xu, Xin‐You Zhou, Ping‐Jie Wei, Jin‐Gang Liu
Abstract
Abstract As an alternative for platinum‐based electrocatalysts, the development of non‐precious metal catalysts for oxygen reduction reaction (ORR) is highly desirable for fuel cell applications. In this paper, we propose a facile preparation method for a B, N‐codoped Cu–N/B–C nanomaterial as an efficient electrocatalyst for ORR in alkaline electrolytes. One‐step heat treatment of cyanamide/melamine, boric acid, and cupric chloride loaded on carbon black produces a Cu–N/B–C composite with a high specific surface area. The Cu–N/B–C‐800 composite pyrolyzed at 800 °C has the best ORR performance among all tested composites. Cu–N/B–C‐800 saw an ORR onset potential at 0.95 V and a half‐wave potential (E 1/2 ) at 0.84 V vs. reversible hydrogen electrode (RHE) in 0.1 M KOH solution, which is comparable to the commercial 20 wt% Pt/C catalyst. Moreover, Cu–N/B–C‐800 has a small negatively shifted E 1/2 value (−8.0 mV) under the accelerated‐durability test condition, demonstrating superior stability and higher tolerance to the methanol‐crossover effect compared with the Pt/C catalyst. Furthermore, the anion exchange membrane fuel cell (AEMFC) loaded with Cu–N/B–C‐800 as the cathode catalyst has an open cell voltage of 0.85 V and a peak power density of 80 mW/cm 2 at 60 °C without backpressure, which is in the list of optimal non‐precious metal catalysts for ORR in AEMFC.