Rational Design of Bimetallic Oxide Multi‐Nanoarchitectures for High‐Rate and Durable Hybrid Supercapacitors
Shaik Junied Arbaz, S. Chandra Sekhar, Goli Nagaraju, Bhimanaboina Ramulu, Jae Su Yu
Abstract
Abstract Designing porous multi‐nanoarchitectures can be advantageous to reduce the ion impregnation and enhance the electrokinetics in the active materials of electrochemical energy storage devices. Herein, the nickel cobaltite (NiCo 2 O 4 ) hybrid nanoarchitecture (NCO HNA) is prepared by using a facile wet‐chemical method, followed by calcination. The effect of surfactants on the evolution of morphology is comprehensively investigated. The NCO HNA prepared with both the carbamide and methenamine as surfactants (NCO‐C+M) demonstrates 1D nanorods along with 2D hexagonal nanosheets. Owing to its advantageous structural features, the NCO‐C+M electrode exhibits maximum areal capacity of 154.7 μAh cm −2 compared to the other electrodes, with decent capacity retention of 86.7% after 10 000 cycles. The hybrid supercapacitor (HSC) device is fabricated with NCO‐C+M as a positive electrode and activated carbon as a negative electrode. The fabricated HSC device delivers a superior areal capacitance of 221.7 mF cm −2 at 1.5 mA cm −2 and still retains 93.2% at a high current density. Besides, the HSC displays a high energy density of 67.8 μWh cm −2 and a high power density of 19545 µW cm −2 , with good cycling efficiency (81.3%) after 10 000 cycles. The practicability of HSC is further tested by powering‐up various electronic components.