Facile electrochemical deposition of Cu7Te4 thin films with visible-light driven photocatalytic activity and thermoelectric performance

Abstract

We report a facile strategy to fabricate thin films of Cu₇Te₄ via a two-electrode galvanic method and demonstrate its application as a recyclable photocatalyst with visible-light-driven photocatalytic activity and photostability. The organic dyes Methylene Blue (MB), and Rose Bengal (RB) and Cr(VI) as a toxic metal ion were chosen to explore the photocatalytic performance. MB was completely degraded (97%) under visible light irradiation in 60 min while RB was degraded up to 92% within 90 min irradiation. Furthermore, the Cu₇Te₄ thin film also showed superior photoactivity to reduce toxic Cr(VI) to Cr(III). The effective removal of Cr(VI) up to 99.8% at pH 2 was observed in 30 min. The related photocatalytic mechanism is discussed based on the active species trapping experiments. In addition, the Cu₇Te₄ thin film shows improved thermoelectric performance at room temperature, which may be attributed to the lower value of thermal conductivity obtained in the present case.