• 文献标题:   Structure-guided Capacitance Relationships in Oxidized Graphene Porous Materials Based Supercapacitors
  • 文献类型:   Article, Early Access
  • 作  者:   GADIPELLI S, AKBARI H, LI JT, HOWARD CA, ZHANG H, SHEARING PR, BRETT DJL
  • 作者关键词:   electric doublelayer capacitance, grapheneoxide, pseudocapacitance, structureperformance relationship, supercapacitor
  • 出版物名称:   ENERGY ENVIRONMENTAL MATERIALS
  • ISSN:  
  • 通讯作者地址:  
  • 被引频次:   0
  • DOI:   10.1002/eem2.12637 EA MAY 2023
  • 出版年:   2023

▎ 摘  要

Supercapacitors formed from porous carbon and graphene-oxide (GO) materials are usually dominated by either electric double-layer capacitance, pseudo-capacitance, or both. Due to these combined features, reduced GO materials have been shown to offer superior capacitance over typical nanoporous carbon materials; however, there is a significant variation in reported values, ranging between 25 and 350 F g(-1). This undermines the structure (e.g., oxygen functionality and/or surface area)-performance relationships for optimization of cost and scalable factors. This work demonstrates important structure-controlled charge storage relationships. For this, a series of exfoliated graphene (EG) derivatives are produced via thermal-shock exfoliation of GO precursors and following controlled graphitization of EG (GEG) generates materials with varied amounts of porosity, redox-active oxygen groups and graphitic components. Experimental results show significantly varied capacitance values between 30 and 250 F g(-1) at 1.0 A g(-1) in GEG structures; this suggests that for a given specific surface area the redox-active and hydrophilic oxygen content can boost the capacitance to 250-300% higher compared to typical mesoporous carbon materials. GEGs with identical oxygen functionality show a surface area governed capacitance. This allows to establish direct structure-performance relationships between 1) redox-active oxygen functional concentration and capacitance and 2) surface area and capacitance.