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

Synthesis and characterization studies of facile CuO:La₂O₃ nanomaterial and its role as electrode for overall energy storage and energy generation applications

Sundus Azhar, Khuram Shahzad Ahmad, Isaac Abrahams, Tenzin Ingsel, Ram K. Gupta, and Adel El-marghany

Materials and Environmental chemistry Lab, Lab E-21, Department of Environmental Sciences, Fatima Jinnah Women University, Rawalpindi, Pakistan

E-mail: chemist.phd33@yahoo.com

Received: 3 August 2023  Accepted: 31 October 2023

Abstract:

The current study implements an environmental-friendly and sustainable methodology to fabricate CuO:La₂O₃-based electrode by using phyto-aqueous extract derived from the Amaranthus viridis plant leaves. CuO:La₂O₃ was synthesized in several concentrations ranging from 2.5 to 10%. The synthesized nanoparticles revealed varied morphology for different concentrations with a varying crystalline size in the range of 18.2–43.44 nm. The lowest optical band gap energy of 3.25 eV was observed for 7.5% doped concentration. Taking advantage of its unique morphology and lower crystalline size, 7.5% CuO:La₂O₃ was specifically selected to be utilized as an electrode material for subsequent investigations involving supercapacitor and water splitting studies. The supercapacitor behavior was studied using cyclic voltammetry (CV) and galvanostatic charge discharge (GCD) techniques. The specific capacitance value of 879.6 F/g was obtained for the fabricated electrode. The water splitting studies revealed the better potential of fabricated electrocatalyst for oxygen evolution reaction with an overpotential value of 351 mV as compared to that of hydrogen evolution reaction where the overpotential value of 182 mV was observed. Moreover, the fabricated electrocatalyst showed excellent cyclic stability for more than 2000 cycles and up to 20 h. Nevertheless, comprehensive findings displayed CuO:La₂O₃ as an efficient energy storage material as well as promising catalytic material for the water splitting studies.

Graphical abstract

Keywords: Nanomaterials; CuO; Lanthanum oxide; Supercapacitor; Water splitting

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-03192-6

Chemical Papers 78 (3) 1647–1658 (2024)