Fluorescence resonance energy transfer and surface Plasmon resonance induced enhanced photoluminescence and photoconductivity property of Au–TiO2 metal–semiconductor nanocomposite

• Successful synthesis process of Au–TiO2 nanocomposite.
• Nanocomposite shows enhanced photoluminescence (PL) and photoconductivity (PC).
• Fluorescence resonance energy transfer (FRET) induced PL has also been discussed.
• Enhanced PL in nanocomposite is combined effect of surface Plasmon and FRET.
• Improved PC is ascribed due to electron accumulation in the nanocomposite.

In this manuscript, we have successfully synthesized Au–TiO2 nanocomposite by sol–gel process. Photoluminescence (PL) and photoconductivity (PC) study have been performed on both bare TiO2 and Au–TiO2 composite samples. We observe enhancement of photoluminescence emission in Au–TiO2 nanocomposite compared to bare TiO2. The enhanced photoluminescence is ascribed owing to combined influence of fluorescence resonance energy transfer and surface Plasmon resonance effect due to presence of Au nanoparticles in nanocomposite sample. Also this nanocomposite exhibits enhanced UV photocurrent because of fluorescence resonance energy transfer by metallic Au attached with TiO2. Interfacial charge transfer can also be realized by the electrochemical impedance spectroscopy results.