Synthesis and Optical Characterization of Mg_1-xNi_xO Nanostructures

Abstract

An attempt has been made here to synthesize nano-powders via sol-gel process. These powders are shown to possess an f.c.c. (NaCl-type) structure with a typical lattice parameter of Å for when decomposition of dried oxalate gel product is carried out at 600°C for 2 h in air. Moreover, they exhibit (i) clusters/agglomerates of nanosize particles and (ii) high BET specific surface area (123.0–135.5 m2/g). Also, the infrared absorption spectra reveal their strong affinity to water. The UV-Vis absorption peaks appearing at ~202 nm, 296 nm, and 379 nm are associated with oxygen defect centres and correspond to the electronic transitions (i) (, , or ), (ii) (, or ) and (iii) (), respectively. The incorporation of Ni2+ ions causes some modifications in the energy levels and the optical absorbance characteristics. The suppression of a strong broad emission peak at 440 nm and improvement of a weak band at 400 nm in the photoluminescence (PL) spectrum arise due to decrease in population density of centres (or F+ dimmers) and emergence of additional F+ centres, respectively with increase in nickel content.

WITHDRAWN: Mg-doped NiO Nanoparticles Decorated Multi-Walled Carbon Nanotube (MWCNT) Nanocomposite and their Biological Activities

“…Finally, the weak absorption peaks around 709-711 cm -1 are related to the stretching vibration of the Ni-O bond in doped NiO. The band at 419 cm -1 is corresponding to the stretching vibrational mode of Mg-O bond [19][20][21][22]. After decorating F-MWCNT with Mg-NiO, it was observed the appearance and disappearance of some absorption peaks in FTIR spectrum.…”

Effects of Precipitation Temperature on Nanoparticle Surface Area and Antibacterial Behaviour of Mg(OH)<sub>2</sub> and MgO Nanoparticles

“…This will assist in lowering the overall cost associated with controlled nanoparticle synthesis. It is however important to note that many methods and their variants have been used to produce MgO nanoparticles [16][17][18][19][20][21][22][23][24].…”

High-Index (Ni,Mg)O Crystallization during Molten Salt Synthesis

“…Lighter colors for samples produced in chloride media may be attributed both to a diluting effect by increasing Mg(II) and to a decreasing concentration of bulk oxygen vacancies, making the material more stoichiometric. 51,65,66 Indeed, the presence of nonstoichiometric Ni 1−x O can explain the dark color of samples produced in nitrates. 65 Samples prepared with 4:1 Mg/Ni ratios, which exhibit the highest color contrast among chloride and nitrate pairings, were compared under optical microscopy using bright field illumination (Figure S2).…”