High‐Density Atomic Fe–N4/C in Tubular, Biomass‐Derived, Nitrogen‐Rich Porous Carbon as Air‐Electrodes for Flexible Zn–Air Batteries

• DOI: 10.1002/adfm.202213897
• Publication Date: 2023-02-23T03:46:03Z
• Authors: Chuanlai Jiao; Zian Xu; Jingze Shao; Yu Xia; Jochi Tseng; Guangyuan Ren; Nianji Zhang; Pengfei Liu; Chongxuan Liu; Guangshe Li; Shi Chen; Shaoqing Chen; Hsing‐Lin Wang
• Keywords: Reversible hydrogen electrode; Oxygen evolution; Carbon fibers

Abstract Developing low‐cost single‐atom catalysts (SACs) with high‐density active sites for oxygen reduction/evolution reactions (ORR/OER) are desirable to promote the performance and application of metal–air batteries. Herein, Fe nanoparticles precisely regulated single atoms supported on waste biomass corn silk (CS) based porous carbon ORR OER. The distinct hierarchical structure hollow tube morphology critical boosting ORR/OER through exposing more accessible sites, providing facile electron conductivity, facilitating mass transfer reactant. Moreover, enhanced intrinsic activity is mainly ascribed high (4.3 wt.%) loading content in as‐synthesized catalyst.Moreover, ultra‐high N doping (10 can compensate insufficient OER conventional FeNC catalysts. When as‐prepared assembled as air‐electrodes flexible Zn–air batteries, they perform a peak power density 101 mW cm −2 , stable discharge–charge voltage gap 0.73 V >44 h, which shows great potential Zinc–air battery. This work provides an avenue transform renewable materials into bifunctional electrocatalysts structure.