Designing TiO2 Nanotubular Arrays with Au-CoO x Core–Shell Nanoparticles for Enhanced Photoelectrochemical Methanol and Lignin Oxidation

• Published in: ACS applied materials & interfaces 2024-09, Vol.16 (37), p.49262-49274
• Main Authors: Sultana, Sabiha, Darowska, Izabela, Pisarek, Marcin, Sulka, Grzegorz D., Syrek, Karolina
• Format: Article
• Language: English
• Subjects: Energy, Environmental, and Catalysis Applications
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.4c07498

One-dimensional (1D) ordered TiO2 nanotubes exhibit exceptional charge transfer capabilities, making them suitable candidates for constructing visible-light-active photoanodes in selective PEC oxidation reactions. Herein, we employed a facile and easily scalable electrochemical method to fabricate Au-CoO x -deposited ordered TiO2 nanotubular array photoanodes. The improved visible light absorption capacity of TiO2-Au-CoO x , with unhampered 1D channels and the controlled integration of Au between TiO2 and CoO x , along with their synergistic interaction, have been identified as the most promising strategy for enhanced PEC performance, as evidenced by an IPCE of 3.7% at 450 nm. Furthermore, the robust interfacial charge transfer pathway from CoO x to the TiO2 surface via the Au mediator promotes the migration of photogenerated electrons and enables the accumulation of holes on the surface of CoO x . These holes are then efficiently utilized by oxidants such as methanol or lignin to generate value-added products, highlighting the potential of this system for advanced PEC applications.