Fe‐N Doped Peanut Shell Activated Carbon as a Superior Electrocatalyst for Oxygen Reduction and Cathode Catalyst for Zinc‐Air Battery

Abstract

AbstractExploring sustainable, low‐cost and high‐performance non‐noble metal (NNM) electrocatalysts as alternatives to Pt‐based catalysts for oxygen reduction reaction (ORR) is crucial for the large‐scale application of metal‐air batteries and fuel cell technology. A new method for preparing ORR catalysts is to use biomass activated carbon supported transition metal. Biomass activated carbon has a highly porous structure which is beneficial to charge and energy transport. In this article, peanut shell activated carbon (PSAC) was prepared as a carrier and iron phthalocyanine (FePc) was the active component of the catalyst. Different mass ratios of the FePc and PSAC were selected for physical doping and then treated at a high temperature. The obtained catalyst FePc/PSAC‐3/1 showed excellent ORR catalytic performance, the onset potential and the half‐wave potential are 0.94 V and 0.85 V respectively, highly comparable to that of commercial Pt/C (20 wt% Pt) catalyst. FePc/PSAC‐3/1 has good stability and better tolerance to the methanol crossover effect than the Pt/C catalyst in alkaline electrolytes. The product was further used as an air cathode to construct the Zn‐air battery at the same time. The excellent recharge‐ability was further evaluated by a 43 h long‐term cycling test without noticeable deterioration for the voltage gap. This work demonstrates the great promise of developing new families of NNM ORR catalysts by the economical and sustainable process.