title: Band Gap Engineering of Boron Nitride by Graphene and Its Application as Positive Electrode Material in Asymmetric Supercapacitor Device.
abstract: Nanostructured hexagonal boron nitride (h-BN)/reduced graphene oxide (RGO) composite is prepared by insertion of h-BN into the graphene oxide through hydrothermal reaction. Formation of the super lattice is confirmed by the existence of two separate UV-visible absorption edges corresponding to two different band gaps. The composite materials show enhanced electrical conductivity as compared to the bulk h-BN. A high specific capacitance of ∼824 F g(-1) is achieved at a current density of 4 A g(-1) for the composite in three-electrode electrochemical measurement. The potential window of the composite electrode lies in the range from -0.1 to 0.5 V in 6 M aqueous KOH electrolyte. The operating voltage is increased to 1.4 V in asymmetric supercapacitor (ASC) device where the thermally reduced graphene oxide is used as the negative electrode and the h-BN/RGO composite as the positive electrode. The ASC exhibits a specific capacitance of 145.7 F g(-1) at a current density of 6 A g(-1) and high energy density of 39.6 W h kg(-1) corresponding to a large power density of ∼4200 W kg(-1). Therefore, a facile hydrothermal route is demonstrated for the first time to utilize h-BN-based composite materials as energy storage electrode materials for supercapacitor applications.
authors.affiliation: ‡Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India.
authors.forename: Sanjit
authors.initials: S
authors.lastname: Saha
authors.affiliation: ‡Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India.
authors.forename: Milan
authors.initials: M
authors.lastname: Jana
authors.affiliation: §Soft Innovative Materials Research Centre, Korea Institute of Science and Technology (KIST), Jeonbuk 565905, South Korea.
authors.forename: Partha
authors.initials: P
authors.lastname: Khanra
authors.affiliation: ‡Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India.
authors.forename: Pranab
authors.initials: P
authors.lastname: Samanta
authors.affiliation: ∥Soft Innovative Materials Research Centre, Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), Jeonbuk 565905, South Korea.
authors.forename: Hyeyoung
authors.initials: H
authors.lastname: Koo
authors.affiliation: ‡Academy of Scientific and Innovative Research (AcSIR), Anusandhan Bhawan, 2 Rafi Marg, New Delhi 110001, India.
authors.forename: Naresh Chandra
authors.initials: NC
authors.lastname: Murmu
authors.forename: Tapas
authors.initials: T
authors.lastname: Kuila
keywords: band gap; boron nitride; energy density; graphene; supercapacitor