Application of pyrolyzed Cobalt (II) tetramethoxyphenyl porphyrin based catalyst in metal-air systems and enzyme electrodes. (1st September 2020)

• Record Type: Journal Article
• Authors: Boukoureshtlieva, R.; Milusheva, Y.; Popov, I.; Trifonova, A.; Momchilov, A.
• Is Part Of: Electrochimica acta. Volume 353(2020)
• Publication Date: 2020-09-01
• Subjects: Metal-air systems -- Enzyme electrodes -- Non-precious metal catalyst -- Cobalt (II) tetramethoxyphenyl porphyrin (CoTMPP) -- Oxygen reduction reaction; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.136472
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: This article presents the use of Cobalt (II) tetramethoxyphenyl porphyrin pyrolyzed on active carbon as a highly efficient non-precious metal catalyst (AC/CoTMPP) for oxygen reduction reaction in three types of electrochemical metal-air systems. The presented results cover various metal-air systems: the alkaline system (zinc-air) with aqueous electrolyte; the neutral (magnesium-air) one with aqueous electrolyte and the non-aqueous (lithium-air) one, as well as one with enzyme electrodes. Pyrolysis of the N4-chelate compound on activated carbon has been shown to produce a stable catalyst over time. The achieved long-term operation (3500 h) in the zinc-air system with alkaline electrolyte is due to increased activity of the AC/CoTMPP catalyst for the decomposition of H2 O2, generated in the process of electrochemical reduction of the oxygen. The use of this catalyst in a magnesium-air system with a NaCl electrolyte is a novelty. Based on the obtained results were mechanically rechargeable magnesium-air cells developed, generating current of 2.5 A–140 A and power of up to 154 W. A novelty is the catalyst use in lithium-air cells with non-aqueous electrolyte. The application of AC/CoTMPP catalyst for enzyme electrodes allows the creation of highly sensitive sensors, designed to operate under anaerobic conditions. AC/CoTMPP has been shown to exhibit its activity over a wide range of potentials (−0.5 V to +1.1 V vs. SHE) in all investigated electrolytes and is active for both the reduction of oxygen and for the oxidation of H2 O2 . Graphical abstract: Some of the experimental cell models, used in various electrochemical systems developed at Institute of Electrochemistry and Energy Systems. Image 1 Highlights: Gas-diffusion electrodes with Cobalt (II) tetramethoxyphenyl porphyrin (CoTMPP) catalyst are developed for use in metal-air systems and enzyme electrodes. Metal-air systems are optimized for use in different electrolytes - alkaline, neutral and non-aqueous. The CoTMPP catalyst demonstrates its catalytic properties over a wide range of potentials. The CoTMPP catalyst is active both for the oxygen reduction and for H2 O2 oxidation.