Synthesis of nanoparticles
Preparation of chromia nanoparticles
Auto ignition process of ammonium dichromate (5 g) was
performed by burning a camphor pellet which was taken along
with ammonium dichromate powder. Self-combustion of ammonium
dichromate took place, thereby yielding a green coloured
chromia powder. The combustion product (nano Cr2O3) was then
separated from the unreacted reactants by soaking in an excess of
distilled water for a period of 2–3 h. The green coloured Cr2O3 nano
particles were later filtered, thoroughly washed with water and
then dried in air. The dried Cr2O3 nano particles were calcinated at
700 8C for 2 h to improve the quality of the sample.