Ag/polydopamine-modified Ti/TiO2 nanotube arrays: A platform for enhanced CO2 photoelectroreduction to methanol

Author(s)

Lima Perini, Joao Angelo ^{[1, 2]} ; Moura Torquato, Lilian D. ^{[1, 2]} ; Irikura, Kallyni ^{[1, 2]} ; Boldrin Zanoni, Maria Valnice ^{[1, 2]}

Affiliation

^[1] Sao Paulo State Univ UNESP, Inst Chem, Araraquara, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Inst Chem, Natl Inst Alternat Technol Detect, Toxicol Evaluat & Removal Micropollutants & Radio, Araraquara, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF CO2 UTILIZATION; v. 34, p. 596-605, DEC 2019.
• Web of Science Citations: 3

Abstract

TiO2 nanotube (NT) arrays were modified with thin films of polydopamine (PDA) and Ag nanoparticles (NP) and were used as electron storage centers on a photoelectrode surface, in order to drive the reduction of CO2 to methanol. Silver nanoparticles were obtained by means of chemical deposition using the catechol groups present in PDA. The Ti/TiO2NT@PDA-AgNP photocathode presented higher photocurrents when irradiated using either UV-vis irradiation or a solar simulator, compared to bare Ti/TiO2NT, indicating improvement of charge carrier separation, while the band gap of the material decreased from 3.12 to 2.3 eV. Under optimized conditions, methanol production of 59.5 mu M cm(-2) was achieved and under the solar simulator, 19.25 mu M cm(-2) of methanol was generated, indicating that the PDA-AgNP coating improved the activation by visible light. The Ag present in the modified Ti/TiO2NT electrodes was quantified during photoelectrocatalysis, with the amount of Ag nanoparticles released from the electrodes being negligible. A schematic representation of the charge transfer mechanism at the Ti/TiO2NT@PDA-AgNP electrode is provided. (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: 16/18057-7 - CO2 reduction aiming to generate value-added compounds by photocatalysis/photoelectrocatalysis using ionic liquid in a pressurized reactor
• Grantee: João Angelo de Lima Perini
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/12790-7 - Preparation and characterization of TiO2 nanostructured electrodes modified with metal organic frameworks (MOFs) for application in the preconcentration and reduction of CO2
• Grantee: Kallyni Irikura
• Support Opportunities: Scholarships in Brazil - Post-Doctoral