Surface Engineering of N‐Doped Carbon Derived from Polyaniline for Primary Zinc‐Air Batteries

Abstract

AbstractZinc‐air batteries (ZABs) with metal‐free cathodes are considered environmentally friendly and cost‐effective. However, more active and durable catalysts are required for this purpose. Herein, polyaniline (PANI)‐derived carbon materials were obtained to boost the oxygen reduction reaction (ORR) and, consequently, the performance of a primary ZAB. The developed porous N‐doped carbon (NDC) materials were engineered by varying the polymerization time and calcination temperature (500–900 °C). SEM micrographs and BET surface areas showed that the polymerization of aniline under cold conditions (5 °C) at 6, 8, or 24 h did not have a significant effect on the morphology or surface area. The fibrous structure of PANI was engineered by temperature, resulting in a progressive increase in the surface area until a three‐dimensional porous structure was achieved at 900 °C with the highest area of 601.9 m2 g−1. The surface doping of nitrogen species shifted from PANI‐rich N species to enriched graphitic N from 12.69 % (500 °C) to 24.26 % at 900 °C. The NDC 900 °C presented a voltage of 1.4 V and power density of 56 mW cm−2 (only 7 mW cm−2 lower than that of Pt/C). The results demonstrate that this material is an excellent candidate for high‐performance primary ZABs.