Novel hafnium oxide-cobalt oxide composite electrode with improved performance for supercapacitor applications
Asifa Mumtaz, Javed Iqbal, Misbah Mumtaz, Hamza Nawaz, Muhammad Ameen
Abstract
In this work, a novel Hafnium oxide (HO) - Cobalt oxide (Co 3 O 4 ) nanocomposite electrode has been proposed that simultaneously combines nanosized architecture, high porosity, and remarkably enhanced electronic conductivity. This versatile combination of high-kappa Hafnium oxide with high-capacity Co 3 O 4 has displayed remarkably improved electrical conductivity via enhanced charge transport kinetics in porous electrode and at interface, a modulated band gap and minimized aggregation of nanoparticles . Benefitting from synergistic effects, the porous electrode has demonstrated an excellent capacitive performance of 1553 Fg −1 at 5 mVs −1 in 2 M NaOH aqueous electrolyte which is almost 6 times higher than neat HO. The nominated electrode has delivered a prominent energy density of 49.16 Wh kg −1 with an adequate power density of 522 W kg −1 . Additionally, the nominated electrode has demonstrated a superior rate performance of 94 % after 3000 cycle operations. Thus, the association of Hafnium oxide with high-capacity Cobalt oxide nanostructures offers an attractive strategy to improve capacitive performance of high-kappa materials in the realm of supercapacitor applications.