Atomic-Scale Engineered Fe Single-Atom Electrocatalyst Based on Waste Pig Blood for High-Performance AEMFCs

Abstract

Biomass is the ideal precursor for fabricating oxygen reduction reaction (ORR) electrocatalysts due to its large-scale and low-cost production, as well as its renewability. Among various forms of biomass, especially waste pig blood is a sustainable precursor for the synthesis of functional electrocatalysts. However, various proteins or metal substances present in the waste pig blood act as impurities and impede the electrocatalytic performance, preventing its direct use as an electrocatalyst. Herein, we report the successful synthesis of hierarchical 2D porous Fe single-atom catalysts on a thermally exfoliated graphene oxide support using hemoglobin-rich red blood cells obtained from purified waste pig blood discarded during the slaughtering process. Because of the widespread Fe single-atom active sites formed via an effective and short heat treatment method and the outstanding mass-transfer properties of the hierarchical porous structure, pig blood-derived carbon (PBC/900/M) showed an excellent ORR performance in alkaline media. Moreover, PBC/900/M was successfully employed as a cathode material in anion exchange membrane fuel cells (AEMFCs) and showed a maximum power density of 658 mW/cm(2), suggesting the remarkable potential for application in AEMFCs. This strategy provides a general approach to prepare a highly efficient single-atom-based catalyst with high performance using abundant biomass as a cost-effective electrocatalyst source.