ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The evaluation of the electrochemical properties of Co₃O₄ nanopowders synthesized by autocombustion and sol–gel methods

S. Kalpana, Vinay S. Bhat, G. Hegde, T. Niranjana Prabhu, and P. N. Anantharamaiah

Department of Chemistry, Faculty of Mathematical and Physical Sciences, M. S. Ramaiah University of Applied Sciences, Bangalore, India

E-mail: niranjan1975@gmail.com

Received: 5 June 2023  Accepted: 15 September 2023

Abstract:

The present investigation involves two synthesis methods, autocombustion (Co₃O₄-AC) and sol–gel (Co₃O₄-SG), for producing nearly spherical-shaped and polygonal shaped nanomaterials of spinel cobalt oxide (Co₃O₄) respectively as electrode materials. TEM image analysis unveiled distinct particle morphologies for the two samples. The Co₃O₄-AC particles exhibited a nearly spherical shape, whereas the Co₃O₄-SG particles displayed a polygonal shape. The phase purity of the Co₃O₄ samples were confirmed via XRD patterns analysis and the crystallite size was calculated to be 44 nm for Co₃O₄-AC and 36 nm for Co₃O₄-SG. The surface area, estimated via BET experiments, of Co₃O₄-AC was found to be 15 m²/g, while Co₃O₄-SG exhibited a slightly lower surface area of 11 m²/g. Co₃O₄-AC exhibited a higher specific capacitance (C_s) of 162 F/g at 0.25 A/g, indicating its superior energy storage capability. On the other hand, Co₃O₄-SG shows a C_s of 98 F/g, indicating slightly lower performance compared to Co₃O₄-AC. Both nanomaterials exhibited better stability, with more than 85% capacity retention after 5000 charge–discharge cycles.

Keywords: Co3O4; Autocombustion; Sol–gel; CV; GCD; Cycle stability

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-03093-8

Chemical Papers 78 (1) 343–356 (2024)