Nano-Micro Letters

MXene-Derived Defect-Rich TiO2@rGO as High-Rate Anodes for Full Na Ion Batteries and Capacitors

Yongzheng Fang1, Yingying Zhang 1, Chenxu Miao 1, Kai Zhu 1, *, Yong Chen 2, Fei Du 3, Jinling Yin 1, Ke Ye 1, Kui Cheng 1, Jun Yan 1, Guiling Wang 1, Dianxue Cao 1, *

Abstract | Support Info
icon-htmlFull Text Html
icon-pdf-smPDF w/ Links
icon-citExport Citation
Figures
+Show more

Nano-Micro Lett. (2020) 12: 128

First Online: 16 June 2020 (Article)

DOI:10.1007/s40820-020-00471-9

*Corresponding author. E-mail: kzhu@hrbeu.edu.cn (Kai Zhu); caodianxue@hrbeu.edu.cn (Dianxue Cao)

 

Abstract

 


Toc

Sodium ion batteries and capacitors have demonstrated their potential applications for next-generation low-cost energy storage devices. These devices’ rate ability is determined by the fast sodium ion storage behavior in electrode materials. Herein, a defective TiO2@reduced graphene oxide (M-TiO2@rGO) self-supporting foam electrode is constructed via a facile MXene decomposition and graphene oxide self-assembling process. The employment of the MXene parent phase exhibits distinctive advantages, enabling defect engineering, nanoengineering, and fluorine-doped metal oxides. As a result, the M-TiO2@rGO electrode shows a pseudocapacitance-dominated hybrid sodium storage mechanism. The pseudocapacitance-dominated process leads to high capacity, remarkable rate ability, and superior cycling performance. Significantly, an M-TiO2@rGO//Na3V2(PO4)3 sodium full cell and an M-TiO2@rGO//HPAC sodium ion capacitor are fabricated to demonstrate the promising application of M-TiO2@rGO. The sodium ion battery presents a capacity of 177.1 mAh g-1 at 500 mA g-1 and capacity retention of 74% after 200 cycles. The sodium ion capacitor delivers a maximum energy density of 101.2 Wh kg-1 and a maximum power density of 10 103.7 W kg-1. At 1.0 A g-1, it displays an energy retention of 84.7% after 10,000 cycles.


 

Keywords

MXene-Ti2CTx, Vacancy oxygen, Self-supporting, TiO2 anodes, Sodium-ion battery and capacitor

 View: Full Text HTML | PDF w/ Links