Potassium ion doped manganese oxide nanoscrolls enhanced the performance of aqueous zinc-ion batteries  

作　　者：Yang Li Xiaoxu Liu Tianyi Ji Man Zhang Xueru Yan Mengjie Yao Dawei Sheng Shaodong Li Peipei Ren Zexiang Shen 

机构地区：[1]Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials,School of Material Science and Engineering,Shaanxi University of Science and Technology,Xi’an 710021,China [2]Division of Physics and Applied Physics,School of Physical and Mathematical Sciences,Nanyang Technological University,Singapore 637371,Singapore

出　　处：《Chinese Chemical Letters》2025年第1期549-555,共7页中国化学快报(英文版)

基　　金：supported by Beijing Synchrotron Radiation 4B9A and 1W2A Work Station in China,National Natural Science Foundation of China(No.52250710161)。

摘　　要：α-MnO_(2) is a potential positive electrode material for aqueous zinc-ion batteries,but its electrochemical performance of zinc storage requires further improvement.In this paper,potassium ion-doped manganese dioxide nanoscrolls(K-MnO_(2))with oxygen vacancy were synthesized by a one-step hydrothermal method.It was observed that the electrochemical specific capacity was 250.9 m Ah/g at a current density of 0.2 C,which was better than the existing commercialα-MnO_(2).At a high current of 1 C,these batteries demonstrate improved cycle stability.Synchrotron radiation and other experiments as well as DFT theoretical calculations provided additional evidence that K doping was efficient in regulating the metal bond type and the mean charge regulation of covalent bonds with oxygen atoms in MnO_(2).When Mn-O and Mn-K bonds are present,K-MnO_(2) showed outstanding adsorption of Zn~(2+)and further enhanced the Zn^(2+)embedding process.Simultaneously,oxygen defects caused by doping boosted the development of the nanoscroll structure,leading to an increase in active sites available for electrochemical reactions and subsequently enhancing the electrical conductivity ofα-MnO_(2).This study exhibits the potential of optimizing materials based on manganese with the introduction of a potassium doping strategy,resulting in improved performance for aquatic zinc-ion batteries,and presents novel perspectives for related research.

关 键 词：Manganese dioxide K^(+) doping Nanoscrolls XAFS Aqueous zinc-ion batteries 

分 类 号：TB383.1[一般工业技术—材料科学与工程] TM912[电气工程—电力电子与电力传动]