Synthesis of CuBO₂ Nano/Microrods via Easy Molten Salt Route and Study of Its Field Emission Properties

Nanostructures of copper based delafossites, which are p-type transparent conducting oxides (p-TCO), are technologically very important. Nanorods of CuBO₂, the latest member in the family of p-TCO, were prepared via easy molten salt method for the first time. The synthesis was optimized by varying the molarity of the precursor and synthesis parameters. The prepared samples were characterized by X-ray diffraction for structural information. Field emission scanning electron microscopy and transmission electron microscopy revealed the morphological nature of the samples. Compositional analyses were performed by energy dispersive analysis of X-rays. UV–vis–NIR spectrophotometric studies determined reflectance of the samples. Growth of CuBO₂ nanorods was correlated with synthesis duration. Photoluminescence properties of the sample were studied using a fluorometer. The electron field emission properties of the samples were measured using our laboratory-made high vacuum setup. Finite element based simulation studies were performed to explain and compare the field emission behavior with experimental outcome. It was observed that FE properties of the CuBO₂ nanorods were governed by both aspect ratio and the roughness of the nanorods.