Highly redox active mesoporous Ni/Co-organic framework as a potential battery type electrode material for high energy density supercapattery. (February 2023) - Khan, Arif
Abstract: Designing potential electrochemically active metal-organic-framework (MOF) electrode materials with controllable structure and versatile nano-geometries are very pivotal to enable the forthcoming generation electrochemical energy storage systems. Among the hydrothermally synthesized materials; Nickel/MOF (NiMOF), Cobalt/MOF (CoMOF) and Nickel-Cobalt/MOF (Ni/CoMOF) with 1:1 of Ni/Co, the binary Ni/CoMOF shows excellent electrochemical performance compared to NiMOF and CoMOF, achieving a distinguished specific capacity of 594.24C g −1 at current density of 1 A g −1 in 3-electrode setup with 67.32 % remarkable rate capability at 10 A g −1 and excellent cyclic durability of 92.7 % after undergoing 5000 charge-discharge cycles. Further, Ni/CoMOF is employed as a positive active electrode material with Activated‑carbon (ActC) and reduced-graphene oxide (rGO) sequentially as negative capacitive type electrode materials to fabricate supercapattery devices. The high cyclically stable and novel Ni/CoMOF||rGO supercapattery unveils a striking specific capacity of 307.45C g −1 contrary to 222C g −1 of Ni/CoMOF||Act-C at 1 A g −1 and exhibits significantly increased energy density of 66.2 Wh kg −1 at power density of 775.13 kW kg −1 . Overall, this synergy of Ni/CoMOF coupled with rGO in a hybrid configuration shows favorable energy storage features to fulfill the soaring renewable energy demands to power the digital world. Graphical abstract: Unlabelled Image Highlights: All MOF materials were synthesized adopting an eco-friendly and facile stepwise hydrothermal method. The b -value 0.50 verifies the claim of mesoporous Ni/CoMOF exhibiting battery type energy storage mechanism. Ni/CoMOF||rGO supercapattery revealed specific capacitance of 307.45C g −1 at 1 A g −1 . Ni/CoMOF||rGO showed exalted energy density of 66.2 Wh kg −1 at power density of 775.13 W kg −1 .