Deposition of TiO2 and Au: TiO2 Film and Their Photoelectrochemical Properties

Farhana Parveen,1,2

Chaitali V. Jagtap,3

Ravi V. Ingle,

Niyamat I. Beedri3 

Basavaraja Sannakki1*Email

1Department of Physics, Gulbarga University, Kalaburgi-585106, India

2Department of Physics, Govt. Degree College, Kalaburgi-585105, India

3Advanced Physics Laboratory, Department of Physics, SP Pune University, Pune 411007, India

Abstract

Gold (Au) nanoparticles were prepared by the electrochemical deposition of aqueous solution of auric chloride (AuCl4) on the titanium dioxide (TiO2) film. Before and after the electrochemical deposition, the TiO2 film was soaked into dye solution of Rose Bengal. It is found that the photoelectrochemical properties were enhanced after the incorporation of Au nanoparticles along the TiO2 film. Generally, the “hot electrons” were the main feature behind such properties and the hot electrons were the results of the incorporation of Au nanoparticles on the TiO2 film that triggered the exothermic chemical process. Here dye molecules acted as a light absorber, where they converted the incoming photons from the sun rays into electron-hole pairs. The electron-hole pairs within TiO2 showed the localized surface plasmon resonance (LSPR). In this process, the collective oscillations of free electrons confined at the metal surface (conductive substrates) were induced when the incoming incident frequency matched with collective oscillations of these free electrons and transferred them to the conduction band of semiconductor. This caused the enhancement of power conversion, i.e., photovoltage and photocurrent.

Deposition of TiO2 and Au: TiO2 Film and Their Photoelectrochemical Properties