Microwave-induced combustion process variables for MgO nanoparticle synthesis using polyethylene glycol and sorbitol

In this study, MgO nanoparticles were prepared by microwave-induced combustion synthesis of magnesium nitrate (as oxidant and MgO precursor) and polyethylene glycol and sorbitol as fuels. The effects of various parameters including the aging time of the precursor gel before combustion, microwave power and fuel-to-oxidant ratio were investigated. Microwave was applied to homogeneously heat the precursor gel. The temperature profile and the composition of the released gases during the combustion process and the carbonaceous deposits on the MgO nanoparticles were studied by FTIR, TGA, Raman spectroscopy, and temperature programmed oxidation (TPO). The MgO samples were calcined at 400 °C for 3 h and characterized using SEM, TEM, BET and PXRD. MgO nanoparticles as small as 4.1 nm were formed using 20% excess of sorbitol and 40% excess of polyethylene glycol as the fuels.