Gas‐Phase Conversion Promising Controlled Construction of Functional ZnF <sub>2</sub> /V <sub>2</sub> CT <sub>x</sub> for Stabilizing Zn Metal Anodes Toward Aqueous Zinc‐Ion Batteries
Xinyue Gao, Yang Liu, Maoqiang Shen, Xuesen Liu, Yanhao Zhao, Linrui Hou, Changzhou Yuan
Abstract
Abstract The practical application of aqueous zinc‐ion batteries (AZIBs) is impeded by notorious side reactions occurring at the zinc anode including zinc dendrite growth, hydrogen evolution reaction and anodic corrosion. To address these issues, ZnF 2 combined with V 2 C MXene composite (ZnF 2 /V 2 CT x ) is in‐situ synthesized from V 2 ZnC MAX through a facile gas‐phase fluorination strategy and utilized as an efficient protective coating layer for Zn anode. The ionically conductive and hydrophobic ZnF 2 inhibits hydrogen evolution reaction and promotes uniform distribution and migration of Zn 2+ . Meanwhile, the electronically conductive V 2 CT x effectively homogenizes the electric field and reduces local current density. Consequently, a stable, dendrite‐free Zn anode with excellent cycling stability (over 2100 h at 3.0 mA cm −2 ) is achieved. Furthermore, ZnF 2 /V 2 CT x coating layer not only significantly improves the reversibility of zinc deposition/stripping, but efficiently reduces the electrochemical polarization. When paired with a zinc vanadate (Zn 2 V 2 O 7 and ZnV 3 O 8 ) cathode derived directly from the gas‐phase oxidation of V 2 ZnC, the full cells exhibit a 1000‐cycle lifespan at 5.0 A g −1 , and superior rate performance (≈237.6 mAh g −1 at 10.0 A g −1 ). This work presents a novel and efficient strategy to controllably construct MAX phase derivatives for next‐generation AZIBs.