Binder free lanthanum doped manganese oxide @ graphene oxide composite as high energy density electrode material for flexible symmetric solid state supercapacitor

• Published in: Electrochimica acta Vol. 335; p. 135613
• Main Authors: Mane, V.J., Malavekar, D.B., Ubale, S.B., Bulakhe, R.N., In, Insik, Lokhande, C.D.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.03.2020; Elsevier BV
• Subjects: Capacitance; Composite; Electrode materials; Electrodes; Flux density; Graphene; La-doping; Lanthanum; Manganese dioxide; Manganese oxides; Microstructure; Nanoparticles; Sodium sulfate; Solid state; Supercapacitors; Symmetric supercapacitor; Thin film; Thin films; α-MnO2; α-MnO2; Symmetric supercapacitor; Composite; Microstructure; La-doping; Thin film
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2020.135613

The present work is about synthesis of La doped (1–5 vol %) manganese oxide (MnO2) @ graphene oxide (GO) composite electrode. The thin films are obtained using a facile and binder free successive ionic layer adsorption and reaction (SILAR) method. The scanning electron microscopic image of 3%La–MnO2@GO composite thin film shows porous spongy-like nanoparticles. Nitrogen desorption analysis shows that mesoporous sheets of 3%La–MnO2@GO exhibits large surface area up to 149 m2 g−1. The highest electrochemical specific capacitance of 729 F g−1 at the scan rate of 5 mV s−1 is obtained for 3%La–MnO2@GO electrode. The 3%La–MnO2@GO thin film electrode exhibits 94% capacitive retention over 5000 CV cycles. The flexible symmetric solid state supercapacitor device of configuration SS/3%La–MnO2@GO/PVA-Na2SO4/3%La–MnO2@GO/SS operating in potential window 1.8 V shows maximum specific capacitance of 140 F g−1 with energy density of 64 Wh kg−1 at power density of 1 kW kg−1 and capacitive retention of 90% after 5000 CV cycles at the scan rate of 100 mVs−1. [Display omitted] •The MnO2, 1, 3, 5% La-doped MnO2 and 3%La–MnO2@GO thin films are synthesized using SILAR method.•The BET specific area of 149.2 m2 g −1 for 3%La–MnO2@GO is higher than that of MnO2 (49.7 m2 g −1) and 3%La–MnO2 (86.4 m2 g −1) samples.•The highest specific capacitance of 729 F g−1 at 5 mV s−1 is obtained for 3%La–MnO2@GO electrode.•A flexible symmetric solid state supercapacitor device showed energy density of 64 Wh kg−1 at power density 1 kW kg−1.