Atomically Dispersed Zincophilic Sites in N,P-Codoped Carbon Macroporous Fibers Enable Efficient Zn Metal Anodes
Yinxiang Zeng, Zhihao Pei, Deyan Luan, Xiong Wen Lou
Abstract
Zn dendrite growth and undesired parasitic reactions severely restrict the practical use of deep-cycling Zn metal anodes (ZMAs). Herein, we demonstrate an elaborate design of atomically dispersed Cu and Zn sites anchored on N,P-codoped carbon macroporous fibers (denoted as Cu/Zn-N/P-CMFs) as a three-dimensional (3D) versatile host for efficient ZMAs in mildly acidic electrolyte. The 3D macroporous frameworks can alleviate the structural stress and suppress Zn dendrite growth by spatially homogenizing Zn 2+ flux. Moreover, the well-dispersed Cu and Zn atoms anchored by N and P atoms maximize the utilization as abundant active nucleation sites for Zn plating. As expected, the Cu/Zn-N/P-CMFs host presents a low Zn nucleation overpotential, high reversibility, and dendrite-free Zn deposition. The Cu/Zn-N/P-CMFs-Zn electrode exhibits stable Zn plating/stripping with low polarization for 630 h at 2 mA cm –2 and 2 mAh cm –2 . When coupled with a MnO 2 cathode, the fabricated full cell also shows impressive cycling performance even when tested under harsh conditions.