Affiliation:
1. College of Physics and Electronic Information Engineering & Ministry‐Province Jointly Constructed Cultivation Base for State Key Laboratory of Processing for Mom‐Ferrous Metal and Featured Materials & Key Laboratory of Nonferrous Materials and New Processing Technology Guilin University of Technology Guilin 541004 P. R. China
2. Guilin University of Aerospace Technology Guilin 541004 P. R. China
3. Guangxi Novel Battery Materials Research Center of Engineering Technology Center on Nanoenergy Research School of Physics Science and Technology Guangxi University Nanning 530004 P. R. China
4. School of Materials Science & Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University Changsha Hunan 410083 P. R. China
Abstract
AbstractWith the wide application of portable electronic devices, zinc–ion hybrid supercapacitors (ZIHCs) have aroused great interest. However, balancing the low‐temperature performance and high energy density of ZIHCs remains a huge challenge. Herein, a zwitterionic hydrogel electrolyte (ZHE) loaded with carboxymethylcellulose and MXene is designed for ZIHCs, which shows excellent frost resistance and high output voltage. Carboxymethylcellulose and MXene enhance the flexibility and conductivity of the zwitterionic hydrogel electrolyte. Moreover, When ZnCl2 is introduced into a gel electrolyte, it induces an increase in the rate of ion transport, which enables a broadening of the operating temperature of the hydrogel (−40 °C–25 °C). As a result, Zn//AC ZIHCs based on ZHE show a high voltage window of 2 V, a high energy density (specific capacity) of 137 Wh kg−1 (247 F g−1), and the potential for wearable devices. This study will provide an effective strategy for the design of hydrogel ZIHCs with wide voltage windows, high energy density, and high practicality.
Funder
National Natural Science Foundation of China