Electrochemical water oxidation by cobalt-Prussian blue coordination polymer and theoretical studies of the electronic structure of the active species

Author(s)

Pires, Bruno M. ^[1] ; dos Santos, Pamyla L. ^[1] ; Katic, Vera ^[1] ; Strohauer, Stefan ^{[1, 2]} ; Landers, Richard ^[3] ; Formiga, Andre L. B. ^[1] ; Bonacin, Juliano A. ^[1]

Affiliation

^[1] Univ Estadual Campinas, Inst Chem, POB 6154, BR-13083970 Campinas, SP - Brazil

^[2] Goethe Univ Frankfurt, Ctr Sci Comp, Max Laue Str 1, D-60438 Frankfurt - Germany

^[3] Univ Estadual Campinas, Inst Phys Gleb Wataghin, BR-13083859 Campinas, SP - Brazil

• Document type: Journal article
• Source: DALTON TRANSACTIONS; v. 48, n. 15, p. 4811-4822, APR 21 2019.
• Web of Science Citations: 2

Abstract

The search for earth-abundant metal-based catalysts for the oxygen evolution reaction (OER) that operates under neutral conditions is a challenge in the field of sustainable energy. Many strategies have been used, and coordination polymers with structures similar to Prussian blue appear to be interesting electrocatalysts due to their efficiency, stability and tunable properties. In this paper, a novel catalyst produced from a cobalt-pentacyanidoferrate precursor is presented and applied in studies of the OER. This material showed a high surface active area and electrocatalytic activity comparable to traditional cobalt hexacyanidoferrate. According to the theoretical calculations, the improvement of these properties is an effect of the framework arrangement and it is not caused by changes of the electronic structure. Further experimental evidence is necessary to determine the active species. However, our results of spin densities obtained from DFT calculations suggest that the active species for water oxidation is the radical Fe(III)CN-Co(III)-O-center dot. (AU)

• FAPESP's process: 17/23960-0 - Study of the mechanism of water oxidation by catalysts operating at pH7 and its incorporation in electrodes printed in 3D
• Grantee: Juliano Alves Bonacin
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/03576-4 - Mechanistic studies in water oxidation catalysis promoted by ruthenium complexes bearing imidazole units
• Grantee: André Luiz Barboza Formiga
• Support Opportunities: Scholarships abroad - Research
• FAPESP's process: 13/22127-2 - Development of novel materials strategic for integrated analytical devices
• Grantee: Lauro Tatsuo Kubota
• Support Opportunities: Research Projects - Thematic Grants