Tailored structure and photoluminescence of substoichiometric molybdenum oxide nanomaterials by doping of gallium oxide

Abstract

Substoichiometric molybdenum oxide (MoO 3- x ) nanomaterials become the promising structure-dependent semiconductor materials. However, the structural tuning of MoO 3- x nanomaterials is still an important challenge. Here we report the tuned MoO 3- x nanostructures via the doping of Ga 2 O 3 in hot filament chemical vapor deposition system. The diverse characterization results indicate that the addition of Ga 2 O 3 in the MoO 3 precursor leads to the doping of Ga 2 O 3 in the MoO 3- x nanostructures and the increase of the MoO 2 component in MoO 3- x nanomaterials. Furthermore, the addition of Ga 2 O 3 improves the regularity of MoO 3- x nanoparticles (NPs) and induces the lattice expansion of MoO 3- x nanostructures. The photoluminescence (PL) properties were measured at room temperature. The PL results exhibit that the synthesized MoO 3- x nanomaterials generate the ultraviolet, blue, green, red and near infrared light due to the bandgap transition, the transition between two sub-bands, the intervalence charge transfer transition and the transition from the intermediate level to valence band, respectively. In addition, the PL results also reveal the PL quenching due to the doping of Ga 2 O 3 , which is related to the reduction of nanocavities, the aggregation of the MoO 3- x NPs and the increase of MoO 2 phase induced by the incorporation of Ga 2 O 3 in the MoO 3- x nanostructures. These achievements can contribute to the tuning of MoO 3 -based nanostructures and the development of next-generation optoelectronic nanodevices based on doping-engineered MoO 3 nanomaterials. • MoO 3- x nanomaterials with a low doping level of Ga 2 O 3 . • Tailored structures of MoO 3- x nanomaterials by doping of Ga 2 O 3 . • Tunable optical properties of Ga 2 O 3 -doped MoO 3- x nanomaterials.