Effect of Strontium Doping on the Band Gap of CeO_2 Nanoparticles Synthesized Using Facile Co-precipitation

摘要

Pure, 3 mol% and 5 mol% Sr-doped cerium oxide nanoparticles were synthesized by facile aqueous co-precipitation method using cerium nitrate hexahydrate and strontium chloride hexahydrate as the precursors without using any capping agent. The synthesized material was characterized by XRD, SEM, EDX, TEM, Raman spectroscopy and UV-Vis spectroscopic techniques. SEM analysis showed agglomeration of the particles. The Debye-Scherrer analysis revealed fluorite structure of the synthesized material with crystallite size in 6-10 nm range. TEM confirmed the spherical morphology of the particles and particle size distribution in the range of 5-8 nm. UV-Vis spectroscopic study revealed that Sr-doping led to increase in the band gap from 3.2 to 3.7 eV and shifting of absorption edge to the lower wavelength. The blue shift in the band gap with the dopant concentration shows that the band gap of doped cerium oxide nanoparticles can be tuned with variation in the dopant concentration.