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High-Energy Lithium-Ion Hybrid Supercapacitors Composed of Perovskite Type BiFeO3/C Anodes and MOF-Derived Carbon Cathodes

Monday, 1 October 2018
Universal Ballroom (Expo Center)
M. Dewan Sr. and S. B. Majumder (Indian Institute of Technology Kharagpur)
A lithium-ion hybrid supercapacitor (Li-HSC) comprising a Li-ion battery type anode and an electrochemical double layer capacitance (EDLC) type cathode has attracted much interest because it accomplishes a large energy density without compromising the power density. But instead of using a conventional Li-ion battery type anode we introduce a perovskite based anodes where ions migrate through the perovskite lattice, allowing for a variety of electrochemical applications. It is still unknown how lithium ions interact with the perovskite structure during the charging discharging process. In this work, carbon coated BiFeO3 (BiFeO3/C) with a unique mesoporous structure is synthesized through autocombustion using glucose as carbon source and metal-organic framework derived carbon (MOF-C) are prepared, adopted as the anode and the cathode for Li-HSCs. The mesoporous BiFeO3/C microspheres exhibit higher Coulombic capacity, excellent rate performance and a long cycling life because of storage reactions based on conversion instead of Li+ insertion or alloying. The BiFeO3/C structure shows a reversible specific capacity of 708 mA h g1 at a current density 10 mAg-1after 100 discharging-charging cycles with excellent rate performance. The MOF-C achieved the specific capacity of 250.9 F g1 at a current density of 0.1 A g1. At a high current density of 2 A g1, 90% of the initial capacity could be retained after 1000 discharging–charging cycles, suggesting excellent cycle stability. The Li-HSC comprising a BiFeO3/C anode and a MOF-C cathode boasts a large energy density with a high power density o and 90% of the capacity is retained at a current density of 2 A g1 after 1000 charging discharging cycles. The high energy and power densities of the Li-HSCs of BiFeO3/C//MOF-C demonstrate a large potential in energy storage.