• 文献标题:   Covalently Coupled Ultrafine H-TiO2 Nanocrystals/Nitrogen-Doped Graphene Hybrid Materials for High-Performance Supercapacitor
  • 文献类型:   Article
  • 作  者:   YANG SH, LIN Y, SONG XF, ZHANG P, GAO L
  • 作者关键词:   nitrogendoped graphene, ultrafine tio2 nanocrystal, hydrogenation, covalent chemical bond, high capacity, supercapacitor
  • 出版物名称:   ACS APPLIED MATERIALS INTERFACES
  • ISSN:   1944-8244 EI 1944-8252
  • 通讯作者地址:   Shanghai Jiao Tong Univ
  • 被引频次:   63
  • DOI:   10.1021/acsami.5b04368
  • 出版年:   2015

▎ 摘  要

Hydrogenated TiO2 (H-TiO2) are considered one of the most promising materials for supercapacitors given its low-cost, high conductivity, and enhanced electrochemical activity. However, the electrochemical performances of H-TiO2 due to lacking suitable structures is unsatisfactory, and thus how to design energetic H-TiO2-based electrode architectures still remains a great challenge. Herein, covalently coupled ultrafine H-TiO2 nanocrystals/nitrogen-doped graphene (H-TiO2/NG) hybrid materials were developed through a simple hydrothermal route followed by hydrogenation. Within this architecture, the strong interaction between H-TiO, nanocrystals and NG sheets via covalent chemical bonding affords high structural stability inhibiting the aggregation of H-TiO, nanocrystals. Meanwhile, the NG matrices function as an electrical highway and a mechanical backbone so that most of well-dispersed ultrafine H-TiO2 nanocrystals are electrochemically active but stable. As a result, the optimized H-TiO2/NG (H-TiO2/NG-B) exhibited high reversible specific capacity of 385.2 F g(-1) at 1 A g(-1), enhanced rate performance of 320.1 F g(-1) at a high current density of 10 A g(-1), and excellent cycling stability with 98.8% capacity retention.