Manipulate the Electronic and Magnetic States in NiCo2O4 Films through Electric‐Field‐Induced Protonation at Elevated Temperature

• DOI: 10.1002/adma.201900458
• Publication Date: 2019-02-27T20:40:38Z
• Authors: Meng Wang; Xuelei Sui; Yujia Wang; Yung‐Hsiang Juan; Yingjie Lyu; Huining Peng; Tongtong Huang; Shengchun Shen; Chenguang Guo; Jianbing Zhang; Zhuolu Li; Hao‐Bo Li; Nianpeng Lu; Alpha T. N'Diaye; Elke Arenholz; Shuyun Zhou; Qing He; Ying‐Hao Chu; Wenhui Duan; Pu Yu
• Keywords: Ferrimagnetism

Abstract Ionic‐liquid‐gating‐ (ILG‐) induced proton evolution has emerged as a novel strategy to realize electron doping and manipulate the electronic magnetic ground states in complex oxides. While study of wide range systems (e.g., SrCoO 2.5 , VO 2 WO 3 etc.) demonstrated important opportunities incorporate protons through ILG, protonation remains big challenge for many others. Furthermore, mechanism intercalation from ionic liquid/solid interface whole film not yet been revealed. Here, with model system inverse spinel NiCo O 4 an increase temperature during ILG forms single but effective method efficiently achieve protonation. Moreover, induces phase transformation ferrimagnetic metallic into antiferromagnetic insulating at elevated temperatures. This shows that environmental is efficient tuning knob ILG‐induced evolution.