High-performance gas-diffusion electrodes for H2O2 electrosynthesis

Author(s)

Cordeiro, Paulo Jorge Marques ; Martins, Alysson Stefan ; Pereira, George Bueno Santana ; Rocha, Fillipe Vieira ; Rodrigo, Manuel Andres Rodrigo ; Lanza, Marcos Roberto de Vasconcelos

• Document type: Journal article
• Source: Electrochimica Acta; v. 430, p. 11-pg., 2022-08-29.

Abstract

The application of gas diffusion electrodes (GDE) modified with carbon black materials at high overpotentials leads to the substantial production of H2O2 via oxygen reduction reaction. The greatest challenge in this process lies in the reduction of the high overpotentials without affecting H2O2 selectivity. One way of circumventing this problem is through the modification of GDEs with coordination compounds. The present work investigates the modification of Printex L6 carbon (CPL6) with different amounts of porphyrin complexes containing the following metallic centers: Mn, Co, Ni, Cu and Zn. The application of 5.0 wt % Co-Porphyrin/CPL6 modifier yielded the best results, with high selectivity for H2O2 generation (90.2%) and marked improvement in catalytic activity (72.6%) compared to CPL6; these positive effects are attributed to the enhancement of both the interaction energy between Co and HOO* reaction intermediate and the effect of the conjugated pi-electrons of the CPL6. The application of the modified GDE led to the electrogeneration of 340 mg L-1 of H2O2 with energy consumption of 86.6 kWh kg(-1) and 92.1% improvement in efficiency compared to the unmodified GDE. Thus, the findings show that the 5.0 wt % Co-Porphyrin/CPL6 modifier is an excellent cathode for application in H2O2 generation and in electrochemical advanced oxidation processes. (AU)

• FAPESP's process: 14/50945-4 - INCT 2014: National Institute for Alternative Technologies of Detection, Toxicological Evaluation and Removal of Micropollutants and Radioactivies
• Grantee: Maria Valnice Boldrin
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 19/11242-1 - Relative quantification of DNA-Topoisomerases enzymes in cell lines: Correlation between cytotoxicity and mechanism of action of coordination compounds
• Grantee: Fillipe Vieira Rocha
• Support Opportunities: Regular Research Grants
• FAPESP's process: 16/04201-9 - Transition metal compounds bearinhg thiosemicarbazones and phosphines as ligand: investigation of cytotoxicity and mechanism of action
• Grantee: Fillipe Vieira Rocha
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/10118-0 - Study and application of electrochemical technology for the analysis and degradation of endocrine interferents: materials, sensors, processes and scientific dissemination
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 20/13088-7 - Modified gas diffusion electrodes applied in the degradation of organic pollutants in a flow electrochemical reactor
• Grantee: Paulo Jorge Marques Cordeiro Junior
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate (Direct)
• FAPESP's process: 17/13123-4 - Development of photoelectrocatalytic membranes based on TiO2 and Al2O3 modified and applied in the treatment of organic contaminants and microorganisms in aqueous solution
• Grantee: Alysson Stefan Martins
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 16/19612-4 - Degradation of endocrine disruptors carbofuran, methylparaben and propylparaben via electrogenerated H2O2 and associated processes (electrogenerated H2O2/UV, electro-Fenton e photoelectro-Fenton)
• Grantee: Paulo Jorge Marques Cordeiro Junior
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 16/01937-4 - Synthesis of binary metal oxides (Nb, Zr, Ta, Ru, Mo and Co) supported on amorphous carbon for the production of gas diffusion electrodes (GDE) for the electrosynthesis of H2O2 in situ in flow reactors.
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Regular Research Grants