Reconstructed Wood Carbon Aerogel with Single-Atom Sites for Flexible Zn–Air Batteries
Zehong Chen, Linxin Zhong, Zhongxin Chen, Hao Zhuo, Xuan Zhao, Haihong Lai, Tingzhen Li, Yang Wu, Zhao‐Qing Liu, Hao Zhang, Emmanuel I. Iwuoha, Kasım Ocakoğlu, Xinwen Peng
Abstract
Single-atom catalysts (SACs) have become vital air cathodes for metal–air batteries, but fabricating monolithic SACs with high catalytic activity and mechanical strength is currently lacking. Herein, an all-natural wood carbon aerogel with single-atom sites is reconstructed via modulating the multi-interactions within lignocellulosic components. Cellulose nanofiber (CNF) constitutes an oriented scaffold via physical interweaving and strong electrostatic repulsion, while lignosulfonate, acting as a multifunctional bioligand, coordinates with metal ions and forms hydrogen bonds with CNF to prevent the agglomeration of adjacent metal atoms. The resulting carbon aerogel features a biomimetic channel-ordered microstructure with M–N 4 active sites (M = Cu, Fe, and Co), leading to outstanding mechanical elasticity and oxygen reduction and evolution activities with a half-wave potential of 0.881 V. Therefore, the SA-Cu@NCA-based aqueous Zn–air battery (ZAB) exhibits a high specific capacity of 779.3 mA h g –1 and long-term stability, while the flexible ZAB with SA-Cu@NCA as an integrated cathode delivers a high specific capacity and impressive operating stability even under harsh structural deformations. This study presents a viable approach for the sustainable production of flexible SACs for wearable and portable electronics.