Self-standing graphitized hybrid Nanocarbon electrodes towards high-frequency supercapacitors

Carbon materials are considered as the ideal electrode materials for supercapacitors due to their diverse structure and nature. However, their poor frequency response is an obstacle to their application in high-frequency supercapacitors. Herein, an ultra-high temperature graphitization process at 28...

Full description

Saved in:

Bibliographic Details
Published in:	Carbon (New York) 2021-11, Vol.185, p.630-640
Main Authors:	Fan, Ya-Feng, Yi, Zong-Lin, Song, Ge, Wang, Zhe-Fan, Chen, Chao-Jie, Xie, Li-Jing, Sun, Guo-Hua, Su, Fang-Yuan, Chen, Cheng-Meng
Format:	Article
Language:	eng
Subjects:	Carbon Carbon nanotubes Conductivity Density functional theory Electrode materials Electrodes Frequency response Graphene Graphene edge Graphitization High-frequency response Hybrid films Ion transport Nanotubes Quantitative analysis Supercapacitors Ultra-high temperature graphitization Ultrahigh temperature
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Carbon materials are considered as the ideal electrode materials for supercapacitors due to their diverse structure and nature. However, their poor frequency response is an obstacle to their application in high-frequency supercapacitors. Herein, an ultra-high temperature graphitization process at 2800 °C is proposed to fabricate carbon nanotubes/graphene hybrid films that are successfully employed as the electrode materials of high-frequency supercapacitors. By rational hybridization, the carbon nanotubes/graphene interlinked networks offer fast ion transport paths. Importantly, via a graphitization process at 2800 °C, the as-obtained hybrid films exhibit an ultrahigh in-plane conductivity of 491.81 S cm−1 and favorable out-plane conductivity of 27.98 mS cm−1. Such design brings the as-constructed high-frequency supercapacitors an unprecedented phase angle (up to −56.23°) and area capacitance (up to 230.56 μF cm−2) at 120 Hz, and their cut-off frequency can be nearly 30 times higher than that of films carbonization at 1600 °C. Such increases, further supported by density functional theory (DFT) calculations, are partly attributable to enhancements of ion response arising from the repair of edge defects of graphene. These findings will provide a new method in designing the structure of carbon electrodes for enhancing SCs frequency response performances. Graphitization is proposed to fabricate carbon nanotubes/graphene hybrid films that are employed as electrode materials for high-frequency supercapacitors. The as-obtained hybrid films exhibit excellent electron and ion transport properties due to high conductivity and few exposed graphene edges. These resulting supercapacitors exhibit excellent rate capability. [Display omitted]
ISSN:	0008-6223 1873-3891