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Updated: Jul 24, 2025
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Enhanced quantum capacitance of MX4(M = Fe, Co, Ni, Cu, and Zn; X = N, P) moieties embedded graphene: a DFT study
Babita Rani1, Vladimir Bubanja2,3, Vijay K Jindal4
1Physics Department, Punjabi University, Patiala 147002, India.
Abstract:
In this work, density functional theory calculations are performed to study the impact of embedding transition metal-(N/P)4moieties in graphene on its geometric structure, electronic properties, and quantum capacitance. Enhancement of quantum capacitance of transition metal doped nitrogen/phosphorus pyridinic graphenes is observed, which is directly related to the availability of states near the Fermi level. The findings show that electronic properties and hence quantum capacitance of graphene can be tuned by varying transition metal dopants and/or their coordination environment. Modified graphenes can suitably be chosen as positive or negative electrodes of asymmetric supercapacitors depending upon the values of quantum capacitance and stored charges. Furthermore, quantum capacitance can be enhanced by widening the working voltage window. The results can serve as guidelines for the design of graphene-based electrodes in supercapacitor applications.
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