Novel cobalt doped hafnium oxide/reduced graphene oxide nanosphere composite materials exhibit superior supercapacitor performance and long cyclic stability. (August 2022)

• Record Type: Journal Article
• Authors: Nethaji, P.; Revathi, P.; Senthil Kumar, P.
• Is Part Of: Sustainable energy technologies and assessments. Volume 52:Part B(2022)
• Publication Date: 2022-08
• Subjects: Hydrothermal -- Nanosphere -- Specific capacitance -- Cyclic stability -- Supercapacitor; Renewable energy sources -- Periodicals; Energy development -- Technological innovations -- Periodicals; Electric power production -- Periodicals; Energy storage -- Periodicals; 333.79
• DOI: 10.1016/j.seta.2022.102167
• Languages: English
• ISSNs: 2213-1388

Abstract

Graphical abstract: Highlights: Novel 6% Co doped HfO2 /rGO nanocomposite were synthesized by a simple single step hydrothermal method. The rGO in the middle of the nanosphere like 6% Co doped HfO2 /rGO can remarkably improve the conductivity. 6% Co doped HfO2 /rGO (1015 F/g) nanocomposite showed higher electrochemical performance compared to 6% Co doped HfO2 (396 F/g). The synthesized electrode of 6% Co doped HfO2 /rGO exhibits 97% capacitance retention after 4000 cycles of long-term cycling stability. Abstract: This paper describes a unique synthesized nanosphere using 6% Cobalt doped hafnium oxide/reduced graphene oxide nanocomposite (6% Co doped HfO2 /rGO) for its feasibility as electrode material in supercapacitor applications utilizing a simple one-step hydrothermal technique. The structural behavior, binding energies, and quality of the synthesized 6% Co doped HfO2 /rGO nanocomposite were exhibited by XRD, FTIR, XPS, and Raman analyses. The 6% Co doped HfO2 nanospheres in the 6% Co doped HfO2 /rGO nanocomposite were coated across the exterior of the rGO sheet, according to HR-SEM and HR-TEM imaging. The 6% Co doped HfO2 /rGO nanocomposite revealed enhanced specific capacitance (1015 F/g at 1A/g), which was compared to 6% Co doped HfO2 (396 F/g at 1A/g) electrode in the redox active 1 M H2 SO4 electrolyte (0.0 to 0.7 V). After 4000 continuous cycles, the electrode material maintained 97 % of its capability and exceptional long-term cyclic stability. The superior super-capacitive performance established the 6% Co doped HfO2 /rGO nanocomposite as a promising electrode for supercapacitor applications.