Studies on Structural Ptical Magnetic and Catalytic Properties of Nd Doped 3d Metal Oxides

Abstract

A series of Nd-doped Mn3O4, Fe3O4, Co3O4 and NiO were successfully newlinesynthesized using a facile microwave method. The physicochemical newlinecharacterizations of the samples were carried out using XRD, FTIR, SEM, newlineTEM, EDX, DRS, PL, VSM and BET studies. The XRD analysis revealed the newlinesuccessful incorporation of neodymium (dopant) ions into the host crystal newlinelattice. The average crystallites size was calculated using Debye-Scherrer newlineformula and a decrease in crystallite size with increasing Nd concentrations was newlineobserved. The surface morphology and particles size were analysed using newlinescanning electron microscopy and transmission electron microscopy. The newlinevariations in particles size were observed with the increasing concentrations of newlinedopant in the host crystal lattice. The UV-Vis DRS studies revealed a reduction newlinein the band gap values of the Nd doped samples in comparison to its pure newlineanalogues. The BET analysis showed increase in surface area of the Nd doped newlinesamples. The Photoluminescence spectral analysis confirmed the presence of newlinedefects in the doped samples. The magnetic properties were studied using newlineVibrating Sample Magnetometer and the analysis revealed the weak newlineferromagnetic properties in the Nd doped Mn3O4, Fe3O4 and NiO samples. The newlinevariations in other magnetic parameters were also observed with changing newlineconcentrations of the dopant. The catalytic efficiency of the prepared samples newlinewas evaluated for the oxidation of styrene to benzaldehyde under different newlinereaction conditions in a batch reactor. The maximum yield of benzaldehyde was obtained using the Nd doped Mn3O4 catalyst. It is concluded that the particles newlinesize, surface area and the presence of defects (Lewis acid sites) are mainly newlineresponsible for the enhancement in the selectivity towards the formation of newlinebenzaldehyde. The recycle studies were performed using the used catalyst. The newlineretention in the catalytic activity was observed for four consecutive cycles.