title: Molecular Origin of Electric Double-Layer Capacitance at Multilayer Graphene Edges.
abstract: Multilayer graphenes have been widely used as active materials for electric double-layer capacitors (EDLCs), where their numerous edges are demonstrated to play a crucial role in charge storage. In this work, the interfacial structure and capacitive behaviors of multilayer graphene edges with representative interlayer spacing are studied via molecular dynamics (MD) simulations. Compared with planar graphite surfaces, edges can achieve a 2-fold increase in the specific capacitance at a wider interlayer spacing of ∼5.0 Å. Unusually, the molecular origins for achieved charge storage are predominantly attributed to the structural evolutions of solvents occurring in the double layer, going beyond the traditional views of regulating the capacitance by ion adsorption/separation. Specifically, diverse ionic distributions exhibit similar screening ability and EDLC thickness, while water molecules can counterbalance the interfacial electric fields more effectively at edge site. The as-obtained findings will be instructive in designing graphene-based EDLCs for advanced capacitive performances.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, College of Energy Engineering, Zhejiang University , Hangzhou, Zhejiang Province 310027, China.|Institute of Mineral Engineering, Division of Materials Science and Engineering, Faculty of Georesources and Materials Engineering, Rheinisch-Westfaelische Technische Hochschule (RWTH) Aachen University , 52064 Aachen, Germany.
authors.forename: Huachao
authors.initials: H
authors.lastname: Yang
authors.affiliation: Institute of Mineral Engineering, Division of Materials Science and Engineering, Faculty of Georesources and Materials Engineering, Rheinisch-Westfaelische Technische Hochschule (RWTH) Aachen University , 52064 Aachen, Germany.
authors.forename: Xiaoliang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, College of Energy Engineering, Zhejiang University , Hangzhou, Zhejiang Province 310027, China.
authors.forename: Jinyuan
authors.initials: J
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, College of Energy Engineering, Zhejiang University , Hangzhou, Zhejiang Province 310027, China.
authors.forename: Zheng
authors.identifier: http://orcid.org/0000-0001-9308-7624
authors.initials: Z
authors.lastname: Bo
authors.affiliation: Institute of Mineral Engineering, Division of Materials Science and Engineering, Faculty of Georesources and Materials Engineering, Rheinisch-Westfaelische Technische Hochschule (RWTH) Aachen University , 52064 Aachen, Germany.|Aachen Institute for Advanced Study in Computational Engineering Science (AICES), RWTH Aachen University , 52062 Aachen, Germany.
authors.forename: Ming
authors.initials: M
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, College of Energy Engineering, Zhejiang University , Hangzhou, Zhejiang Province 310027, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Yan
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, College of Energy Engineering, Zhejiang University , Hangzhou, Zhejiang Province 310027, China.
authors.forename: Kefa
authors.initials: K
authors.lastname: Cen