Substrate-dependent photocatalytic properties of electrochemical deposited Cu2O heterojunction
Riza Ariyani Nur Khasanah1*
1Applied Physics, Tunghai University, Taichung, Taiwan
* Presenter:Riza Ariyani Nur Khasanah,
Cu2O is a promising material for photocatalysis because of its absorption ability in the ultraviolet (UV)-visible light range. Cu2O deposited on conductive Ti and fluorine-doped tin oxide (FTO) substrates behaves as a photocathode. Cu2O deposited on an n-type semiconductor such as TiO2 nanotube arrays (TNA) behaves as a photoanode and has demonstrated better photocatalytic activity than that of TNA. The substrate-dependent photocatalytic property of Cu2O heterojunctions remain unclear. In this work, the photocatalytic properties of a Cu2O/TNA junction as a photoanode and of Cu2O/Ti and Cu2O/FTO junctions as photocathodes without bias were systematically studied to understand their performance. The Cu2O/TNA photoanode exhibited greater photocurrent spectral responses, which obviously outperformed the Cu2O/Ti and Cu2O/FTO photocathodes. The photoanodic/photocathodic properties of those junctions were depicted in their energy diagrams. Time-resolved photoluminescence indicated that no improved charge separation occurred at the Cu2O/TNA, Cu2O/Ti, and Cu2O/FTO junctions. The improved photocatalytic properties of Cu2O/TNA compared with TNA was attributed to the UV-visible light absorption of Cu2O.

Keywords: Substrate-dependence, Photocatalytic properties, Cu2O, TiO2 nanotube arrays, heterojunction