Reactive sputtering deposition of Co3O4 films and an evaluation of its use as an electrochemical sensor for ascorbic acid

Author(s)

Azevedo Neto, Nilton Francelosi ; Angelico, Joao C. ; da Silva Pelissari, Marcelo R. ; Camargo, Luan Pereira ; Simoes, Rafael Plana ; Dall'Antonia, Luiz Henrique ; Dias da Silva, Jose Humberto

• Document type: Journal article
• Source: JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS; v. 33, n. 24, p. 15-pg., 2022-08-03.

Abstract

Co3O4 films have been deposited using reactive DC magnetron sputtering onto fluorine-doped tin oxide (FTO) and fused silica (SiO2). X-ray diffraction measurements confirmed the spinel Co3O4 phase. The surface roughness of the films were 4 nm and 20 nm for SiO2 and FTO substrates, respectively, as measured by atomic force microscopy. Optical transmission spectra of Co3O4 films show strong absorption in the near-infrared and visible regions. The photoconductivity response of SiO2/Co3O4, using 405 nm excitation, measured at room temperature is much smaller than the observed at 10 K. The electrochemical activity of the FTO/Co3O4 for the oxidation reaction of the ascorbic acid (AA) was investigated by differential pulse voltammetry and chronoamperometric. A model for the oxidation, based on density functional theory calculations for the electronic structure of the AA, is proposed. The set of results show that the assembled FTO/Co3O4 electrode can be used as an alternative and remarkable-performance non-enzymatic device to ascorbic acid electrooxidation. (AU)

• FAPESP's process: 20/12356-8 - Stability optimization of perovskite solar cells
• Grantee: Carlos Frederico de Oliveira Graeff
• Support Opportunities: Research Projects - Thematic Grants