Effect of Co/Nd co-doping on the structural, optical, and morphological properties of ZnO nanorods grown on silicon substrate Si (100) by hydrothermal method

In this study, single-doped (cobalt (Co), neodymium (Nd)), and co-doped (Co/Nd) ZnO thin films were fabricated through the hydrothermal method on a silicon substrate (100) and investigated structural, morphological, and optical characteristics. In this work, tunable bandgap engineering of single-phase Co/Nd co-doped ZnO nanorods was reported to be controlled through variation of dopant concentrations. The concentration of neodymium varies as 4, 8, and 12 % by weight, while cobalt is fixed up to 4 %. XRD confirms the phase purity and high crystalline nature of the prepared nanorods. The physical structural parameters such as-fabricated nanorods were investigated in detail. Furthermore, Scherrer, Williamson-Hall (W–H), and size-strain plot (SSP) methods were used to investigate the crystallite size and lattice strain. The optical parameters like absorbance (A), transmittance (%T), energy bandgap (Eg), skin depth (δ), optical density (Dopt), optical conductivity (σopt), Urbach energy (Eu), and extinction coefficient (k), were investigated by UV–vis spectra. This study shows that grown films are suitable for modern optoelectronic applications.