A simple strategy to incorporate Pt into TiO2 nanosponges via wet oxidation of multilayered films

Abstract

Addition of noble metals has been shown to enhance the properties of TiO₂ for a wide range of applications. Methods to incorporate Pt into TiO₂ usually involve the use of chloride-containing precursors. Here we present an alternative chloride-free method to incorporate Pt through aqueous oxidation of multilayered Ti/Pt/Ti films in a simple manner. In this contribution, we demonstrate this route using sputtered Ti/Pt/Ti films either in blanket layer or micrometer scale features patterned using lithography. A mechanism for Pt incorporation into TiO₂ based on formation of Pt hydroxides is proposed. We demonstrate the utility of this technique to incorporate Pt into TiO₂ nanosponges by constructing prototype sensors which exhibit a faster response time and a current increase of 2 orders of magnitude larger than sensors using pristine TiO₂ nanosponges. This method is a simple route to integrate Pt-modified TiO₂ (Pt-TiO₂) nanosponge features into devices such as lab on a chip and integrated power sources.