Ultrahigh rate capability of 1D/2D polyaniline/titanium carbide (MXene) nanohybrid for advanced asymmetric supercapacitors

• Published in: Nano research 2022, Vol.15 (1), p.285-295
• Main Authors: Zhou, Jinhua, Kang, Qi, Xu, Shuchi, Li, Xiaoge, Liu, Cong, Ni, Lu, Chen, Ningna, Lu, Chunliang, Wang, Xizhang, Peng, Luming, Guo, Xuefeng, Ding, Weiping, Hou, Wenhua
• Format: Article
• Language: English
• Subjects: Asymmetry; Atomic/Molecular Structure and Spectra; Biomedicine; Biotechnology; Capacitance; Chemistry and Materials Science; Composite materials; Condensed Matter Physics; Design; Electrochemistry; Electrode materials; Electrodes; Electrolytes; Energy storage; Flux density; Graphene; Kinetics; Laboratories; Materials Science; MXenes; Nanofibers; Nanotechnology; Polyanilines; Polymerization; Research Article; Retention; Self-assembly; Stability analysis; Supercapacitors; Titanium; Titanium carbide
• ISSN: 1998-0124; 1998-0000
• DOI: 10.1007/s12274-021-3472-2

High energy density and enhanced rate capability are highly sought-after for supercapacitors in today’s mobile world. In this work, polyaniline/titanium carbide (MXene) (PANI/Ti 3 C 2 T x ) nanohybrid is synthesized through a facile and cost-effective self-assembly of one-dimensional (1D) PANI nanofibers and two-dimensional (2D) Ti 3 C 2 T x nanosheets. PANI/Ti 3 C 2 T x delivers greatly improved specific capacitance, ultrahigh rate capability (67% capacitance retention from 1 to 100 A·g −1 ) as well as good cycle stability. Electrochemical kinetic analysis reveals that PANI/Ti 3 C 2 T x is featured with surface capacitance-dominated process and has a quasi-reversible kinetics at high scan rates, giving rise to an ultrahigh rate capability. By using PANI/Ti 3 C 2 T x as positive electrode, an 1.8 V aqueous asymmetric supercapacitor (ASC) is successfully assembled, showing a maximum energy density of 50.8 Wh·kg −1 (at 0.9 kW·kg −1 ) and a power density of 18 kW·kg −1 (at 26 Wh·kg −1 ). Moreover, an 3.0 V organic ASC is also elaborately fabricated by using PANI/Ti 3 C 2 T x , achieving an ultrahigh energy density of 67.2 Wh·kg −1 (at 1.5 kW·kg −1 ) and a power density of 30 kW·kg −1 (at 26.8 Wh·kg −1 ). The present work not only improves fundamental understanding of the structure-property relationship towards ultrahigh rate capability electrode materials, but also provides valuable guideline for the rational design of high-performance energy storage devices with both high energy and power densities.