Excitation-induced tunable luminescent properties of polyhedral CaMoO_4 microcrystallites

摘要

Polyhedral CaMoO_4 microcrystallites with excitation-induced tunable luminescent characteristics were successfully synthesized by a hydrothermal method. Polyhedral morphologies with different shapes and exposed facets were observed for the samples prepared at different temperatures. Sharp-vertex polyhedron was obtained at 140 °C due to the increase of (001) surface energy and the sample exhibited the strongest PL emission intensity due to its regular polyhedron morphology. Green and blue light emissions were observed separately under different excitation wavelengths in single CaMoO_4 microcrystallites, which can be attributed to the charge transfer transitions within the [MoO_4]~(2-) complex and the shallow defects in the bandgap, respectively. The excitation-induced tunable luminescent characteristics make it to be a promising inorganic single-emitting component for optical applications.