Cobalt-doped zinc glycolate as a precursor for the production of Zn<sub>1-x</sub>Co<sub>x</sub>O oxide with nanostructured octahedral particles: synthesis, crystal structure, thermal, spectral, and optical properties

Krasil’nikov, V. N.; Tyutyunnik, A. P; Baklanova, I. V.; Gyrdasova, O. I.; Zhukov, V. P.; Chulkov, E. V.; Krasil’nikov, V. N.; Tyutyunnik, A. P; Baklanova, I. V.; Gyrdasova, O. I.; Zhukov, V. P.; Chulkov, E. V.

doi:2023.60.6.990

J. Korean Ceram. Soc. > Volume 60(6); 2023 > Article

Original Article

Journal of the Korean Ceramic Society 2023;60(6): 990-1009.
doi: https://doi.org/10.1007/s43207-023-00323-3

Cobalt-doped zinc glycolate as a precursor for the production of Zn_1-xCo_xO oxide with nanostructured octahedral particles: synthesis, crystal structure, thermal, spectral, and optical properties

V. N. Krasil’nikov¹, A. P Tyutyunnik¹, I. V. Baklanova¹, O. I. Gyrdasova¹, V. P. Zhukov¹, E. V. Chulkov^2,3,4

¹Institute of Solid State Chemistry UB RAS, Ekaterinburg, Russia
²Laboratory of Electronic and Spin Structure of Nanosystems, St. Petersburg State University, St. Petersburg, 198504, Russia
³Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Facultad de Ciencias Químicas, Universidad del País Vasco (UPV-EHU), Apdo. 1072, E-20080, San Sebastián/Donostia, Spain
⁴Donostia International Physics Center (DIPC), Paseo de Manuel Lardizabal 4, E-20018, San Sebastián/Donostia, Spain

Correspondence

I. V. Baklanova ,Email: baklanova_i@ihim.uran.ru

Received: August 24, 2023; Revised: August 1, 2023 Accepted: August 4, 2023. Published online: August 22, 2023.

ABSTRACT

In this paper, the results of studying the formation conditions, crystal structure, thermal, spectral, and optical properties, as well as the electronic band structure of cobalt-doped zinc glycolate Zn_1-xCo_x(OCH₂CH₂O) (0^<x ≤ 0.2) are presented. Using X-ray powder diffraction data, it was shown that solid solutions are obtained by partial substitution of cobalt for zinc, while maintaining the crystal structure of Zn(OCH₂CH₂O). The vibrational spectra of Zn_1-xCo_x(OCH₂CH₂O) are identical to those of Zn(OCH₂CH₂O) and correlate completely with the results of structural analysis. As a result of heating in air at 600–900 °C, glycolate Zn_1-xCo_x(OCH₂CH₂O), where 0^<x ≤ 0.1, turns into oxide of the composition Zn_1-xCo_xO with wurtzite structure, whose powders have a deep green color (Rinman’s green). The UV-Vis-NIR spectra of Zn_1-xCo_xO contain bands typical of Co²⁺ ion transitions in the tetrahedral environment. When Zn_1-xCo_x(OCH₂CH₂O) is heated in helium atmosphere, composites (1-x)ZnO:xCo:nC are formed that include a phase with wurtzite structure, metallic cobalt, and elemental carbon. The electronic band structure, optical characteristics, and isosurfaces of wave functions of pure and cobalt-doped zinc glycolate and oxide were calculated. This allowed us to establish the reasons for the increase in the band gap width in glycolate compared to the oxide and its decrease during doping.

Key words: Zinc glycolate · Zinc oxide · Cobalt · Crystal structure · Optical properties · First-principle calculations