Preparation and optical property of gallium zinc oxynitride powder and nanocrystals with sawtooth-like appearance

Abstract

Gallium zinc oxynitride powder and its nanocrystals were obtained by nitridation of a ZnGa 2 O 4 precursor under NH 3 flow. The nitrided powder had the chemical composition of (Ga 0.75 Zn 0.23 □ 0.02)(N 0.71 O 0.29), where □ indicates a vacancy, and showed improved crystallinity with a decrease in cationic vacancies compared to that for pristine gallium oxynitride without zinc. Gallium zinc oxynitride nanocrystals with rod-like morphology were obtained by nitridation of the oxide precursor on a NiO pellet. The nanorod crystals were several hundred nanometers wide and several micrometers long. The nanorods had a sawtooth appearance with triangular grains aligned along the length direction of the rods. The nanocrystals with a chemical composition of Ga/Zn = 0.80/0.20 exhibited a broad cathodoluminescence emission at 2.1 eV, similar to the powder products.