Enhanced photoluminescence of potassium-doped tungsten oxide by acetone exposure

Abstract

Studies of optical properties of doped nanocrystals of tungsten trioxide can elucidate new information about the material. A novel molecule-enhanced photoluminescence (PL) of potassium-doped tungsten trioxide (K_xWO) was explored in the presence of different gases to understand charge transfer between molecules and K_xWO on the properties of the material. We performed Raman spectroscopy and PL experiments in the presence of gaseous acetone or ethanol mixed with other gases (N₂ and O₂). PL at 630 nm from K_xWO was observed and further enhanced when the sample was continuously irradiated with a 532 nm CW laser in acetone. A mechanism of strong emission of the PL induced by the charge transfer between the acetone and the K_xWO is proposed.