Facile fabrication of binder-free reduced graphene oxide/MnO2/Ni foam hybrid electrode for high-performance supercapacitors

• Published in: Journal of alloys and compounds Vol. 812; p. 152124
• Main Authors: Zhao, Zhiyong, Shen, Ting, Liu, Zhihua, Zhong, Qishi, Qin, Yujun
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.01.2020; Elsevier BV
• Subjects: Aerogels; Binder-free; Capacitance; Electrochemical deposition; Electrode materials; Electrodes; Flux density; Graphene; Graphene aerogel; Manganese dioxide; Maximum power density; Metal foams; MnO2; Supercapacitor; Supercapacitors; MnO2; Electrochemical deposition; Supercapacitor; Graphene aerogel; Binder-free
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.152124

A novel three-dimensional reduced graphene oxide aerogel and MnO2 (rGO/MnO2) hybrid is prepared via a mild method and freeze-drying treatment, followed by an electrodeposition process. The characterization results reveal that the deposited MnO2 is homogeneously anchored on the graphene sheets, which is served as binder-free electrode material to fabricate high-performance supercapacitor. The specific capacitance of rGO/MnO2 on Ni foam reaches 288 F g−1 at 0.5 A g−1. The assembled symmetrical rGO/MnO2/Ni supercapacitor exhibits a maximum energy density of 26.82 Wh kg−1 and a maximum power density of 8.61 kW kg−1, whose capacitance retention maintains 94.7% over 1000 cycles. Moreover, it can successfully activate different LEDs after being charged. These appreciable performances are primarily put down to the cooperative effect of porous structure of rGO/MnO2 and pseudocapacitive property of MnO2, which provides adequate electroactive sites and facilitates the electron/ion transfer during the electrochemical processes. •Hybrid materials based on the reduced graphene oxide and MnO2 are fabricated through a facile process.•The flower-like MnO2 is uniformly electrochemically deposited on graphene aerogel.•The graphene/MnO2/Ni hybrid is used as binder-free electrode for high-performance supercapacitor.•The assembled symmetrical supercapacitors could successfully light up LEDs.