Structural, morphological and optical properties of Ni-doped CeO2 nanospheres prepared by surfactant free co-precipitation technique

Abstract

A high qualitative material is indeed depends on the technique utilized during its preparation as well as its composition. This is because particles do interact to form agglomerates, and in consequence, produce particles with deteriorated quality. In this study, ceria and Ni doped ceria nanospheres (NSs) were prepared using a surfactant free precipitation and co-precipitation techniques, respectively. The prepared samples were characterized using XRD, SEM, EDX, UV-VIS and FTIR. XRD pattern of the undoped ceria confirms the formation of a fluorite cubic structure of ceria and the absence of additional phase in the XRD patterns of the doped ceria samples implies that the ceria cubic structure is retained. FE-SEM analysis revealed that samples possess spherical morphology. Both the average crystallite sizes and the average particle diameters of the samples were found to occur within nano-range. UV-Vis analysis reveals that samples demonstrated excellent optical properties. The optical band gap of the undoped ceria was found to increase with doping 3% and 5% Ni, which could be due to Burstein- Moss effect. However, doping 1% Ni was found to reduce the optical band gap of the undoped ceria, which could be associated with the reduction of the average crystallite size and therefore, is regarded as the optimum dopant. EDX analysis confirms the presence of the cerium, oxygen as well as the expected doping concentrations of the Ni precursor. FTIR analysis shows the presence of O-H stretching vibrations in all samples. Therefore, these nanostructures with such enhanced properties could be utilized as potential materials in a number of electronic and catalytic applications.