Facile route to straight ZnGa2O4 nanowires and their cathodoluminescence properties

Single-crystalline ZnGa2O4 nanowires with high purity were grown on the Au and amorphous carbon layers coated Si substrates by a facile carbothermal reduction process. These ZnGa2O4 nanowires were straight along their growth direction, and the length and diameter were around 10 μm and 150 nm, respectively. The growth mechanism follows an enhanced vapor–liquid–solid (VLS) process. The carbon layers predeposited on the substrates can strongly enhance the VLS growth process of ZnGa2O4 nanowires. The cathodoluminescence (CL) spectrum of an individual nanowire exhibits a broad emission band centered at 537 nm, which can be ascribed to a large quantity of ionized oxygen vacancies.