A study has unveiled exciting advancements in the customization of nickel oxide (NiO) nanopowders, which are now being engineered with improved optical, magnetic, and structural properties through doping. Research has shown how incorporating elements such as chromium, iron, cobalt, copper, and zinc can significantly affect these characteristics, enhancing their potential applications in optoelectronic devices.
The research, carried out using the co-precipitation synthesis method, yielded both pristine and doped formulations of NiO nanopowders. The scientists utilized X-ray powder diffraction (XRD) to analyze the phase formation and structural characteristics of the samples. They confirmed the retention of a face-centered cubic structure across all samples, without indicating any secondary phase formation from the dopants.
Utilizing the Debye-Scherrer formula, the crystallite size of the samples was estimated to range from 16 to 28 nm—an aspect deemed suitable for investigating doping effects. Tests with field emission scanning electron microscopy (FE-SEM) reinforced the results, providing insights on the samples’ morphology and the successful incorporation of elements like Fe and Zn.
Fourier Transform Infrared Spectroscopy (FTIR) was employed to assert the purity of the samples, showcasing the vibrational modes within the metal oxide bonds. The optical properties were assessed using diffuse reflectance spectroscopy, indicating band gap values ranging from 2.77 to 3.46 eV. Notably, the research highlighted how the introduction of doping elements resulted in varied shifts; all dopants led to red shifts except for the zinc variant.
Magnetic properties were probed utilizing the vibrating sample magnetometer (VSM), which revealed room-temperature ferromagnetism present across all samples. The coercivity parameters increased with doping, with the pristine NiO at 80.44 Oe, which surged to 350.75 Oe for the zinc-doped variant. The study emphasized the transition of magnetic behavior, particularly with iron, which shifted from weakly ferromagnetic to distinctly ferromagnetic states.
The broad relevance of these findings indicates significant advantages for applications including data storage, sensor technologies, and electrochromic devices. Each dopant contributes uniquely to the nanopowders’ structural and functional characteristics, offering fertile ground for future research and technological advancements.
This investigation stands as an important step forward in the enhancement of nickel oxide materials, positioning them at the forefront of cutting-edge optoelectronic applications.