ROLE OF CALCINATION TEMPERATURES ON THE STRUCTURAL AND OPTICAL PROPERTIES OF NiO NANOPARTICLES

Nickel oxide nanoparticles (NiO NPs) were synthesized through template free sol-gel method. Synthesized particles were calcined at 300 degrees C, 500 degrees C and 700 degrees C for 2 h and further the particles were characterized for its thermal, functional, structural, morphological and optical properties. The peak broadening analysis was undertaken in order to calculate the variation in size and strain components of the particles with the calcinations temperature. The Debye-Scherer, Williamson-Hall and Sizestrain plot methods were employed in peak broadening analysis and were compared with TEM results. All the NiO NPs crystallite size and lattice strain value were found to be in good agreement with all the models. The TEM analysis revealed that the calcinations at 700 degrees C NiO NPs have sphere like structure of less than 20 nm particles size value. The strong peak observed at 360.5 nm bandgap emission relates to the bandgap of 3.44 eV which is because of the near band edge emission.