Gold nanocluster-sensitized TiO2 nanotubes to enhance the photocatalytic hydrogen generation under visible light

• Published in: Journal of power sources Vol. 287; pp. 150 - 157
• Main Authors: Wang, Hongkai, Chen, Fuyi, Li, Weiyin, Tian, Tian
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-08-2015
• Subjects: Glutathione-protected gold clusters; Hydrogen generation; Metal nanoclusters; Photocatalytic effects; Photocatalytic effects; Hydrogen generation; Glutathione-protected gold clusters; Metal nanoclusters
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2015.04.054

The wide band-gap of TiO2 semiconductors hinders the photocatalytic hydrogen generation under visible light. In this research, we introduce glutathione-protected gold (Au-GSH) nanoclusters as a sensitizer to extend the active region of TiO2 up to a wavelength of 510 nm under visible light spectrum. We demonstrate that Au-GSH nanoclusters are capable of enhancing photocatalytic effects for hydrogen generation in photo-electrochemical cells (PECs). The combined effects of metal nanoclusters and sacrificial agent (EDTA) enhance the photocurrent up to six times more than what can be achieved using Au-GSH nanoclusters without EDTA. Moreover, the mechanisms of interaction between Au-GSH nanoclusters and EDTA have been investigated through instantaneous photoresponse measurements. A single electrode system has been designed to simplify PECs for hydrogen generation, which exhibits the same enhanced photocatalytic effect.
•A novel class of Au-GSH cluster was observed to enhance H2 generation in the visible.•Two kinds of TiO2 nanotube were designed to explore the potential of Au-GSH cluster.•The cooperation adding EDTA produced a photocurrent 6 times higher than Au-GSH alone.•The enhancement mechanism was synergistically confirmed by a simplified PEC system.