Iron-based nanocomposites implanting in N, P Co-doped carbon nanosheets as efficient oxygen reduction electrocatalysts for Zn-Air batteries

Abstract

Reasonable design and construction of efficient and cost-effective oxygen reduction reaction (ORR) electrocatalysts are vital for promoting the practical application of zinc-air batteries (ZABs). Herein, we reported a one-pot self-assemble approach in combination with pyrolysis to prepare nanocomposite electrocatalyst comprised of atomically dispersed Fe-Nx sites and uniformly implanted FeP nanoparticles, which supported on N, P co-doped porous carbon nanosheets (denoted as 2D-FeP@FeNC-900). The 2D-FeP@FeNC-900 exhibits large specific surface area and hierarchical porous structure, along with unique incorporation of FeP, Fe-Nx and N, P co-doping provides abundant active sites and favorable synergistic effect, imparting 2D-FeP@FeNC-900 superior kinetic and electrocatalytic activity towards ORR. Meanwhile, the 2D-FeP@FeNC-900 displays an advantage of methanol-resistance over benchmark Pt/C catalyst. Moreover, the ZABs with 2D-FeP@FeNC-900 achieve superior discharge power density of 260 mW cm−2, specific capacitance of 803.7 mA h g−1, and excellent cyclic stability (when combined with RuO2) of over 130 h, surpassing those of Pt/C counterpart. This work provides an effective and generalizable strategy for engineering metal-compound and atomic-sites on dual-doped nanocarbon matrix for sustainable energy conversation and storage devices.