B, N-codoped Cu-N/B-C Composite as an Efficient Electrocatalyst for Oxygen-Reduction Reaction in Alkaline Media

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 degrees 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 degrees C without backpressure, which is in the list of optimal non-precious metal catalysts for ORR in AEMFC.