Enhancing the electrical conductivity and the dielectric features of ZnO nanoparticles through Co doping effect for energy storage applications

• Published in: Journal of materials science. Materials in electronics Vol. 34; no. 2; p. 116
• Main Authors: Saadi, Hajer, Benzarti, Zohra, Sanguino, Pedro, Pina, João, Abdelmoula, Najmeddine, de Melo, João Sérgio Seixas
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.01.2023; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemical precipitation; Chemical synthesis; Chemistry and Materials Science; Cobalt; Composition; Crystal structure; Crystallites; Dielectric properties; Doping; Electrical resistivity; Energy storage; Materials Science; Morphology; Nanoparticles; Optical and Electronic Materials; Optical properties; Structural analysis; Thermal analysis; Wurtzite; Zinc oxide
• DOI: 10.1007/s10854-022-09470-5
• ISSN: 0957-4522

In this research paper, the undoped and Co-doped ZnO nanopowders were effectively synthesized by the chemical co-precipitation process. The crystal structure, morphological, vibrational, optical and dielectric properties of the as-elaborated samples were characterized by various experimental techniques. This study investigates the impact of cobalt doping on the different characteristics of ZnO nanopowders. Besides, the structural analysis revealed the formation of the hexagonal wurtzite structure for all the compositions. A notable secondary phase corresponding to ZnCo 2 O 4 was clearly observed for the Zn 0.97 Co 0.03 O and Zn 0.95 Co 0.05 O nanopowdered samples. The average crystallite size was found to increase with increasing Co doping concentration. Furthermore, the optical properties demonstrated the narrowing of the optical bandgap energy under Co doping effect. Concerning the morphological properties, the morphology of ZnO nanoparticles was highly influenced by Co doping concentration. A noted change was obtained from spherical shape for undoped ZnO and Zn 0.99 Co 0.01 O to rods shape for Zn 0.97 Co 0.03 O and Zn 0.95 Co 0.05 O compositions. The dielectric analysis showed that both dielectric constant and electrical conductivity increase with the addition of Co doping element into ZnO host lattice. The improvement of structural, optical and dielectric characteristics of Co-doped ZnO nanopowders enhances the performance of these compositions for energy storage applications.