Sonosynthesis of super-alkaline calcium-strontium oxide nanoparticles: Size, morphology, and crystallinity affected the catalytic activity

Abstract

For the first time, nanoparticles of calcium-strontium oxide were synthesized via ultrasound and entirely characterized by different methods. Particles synthesized in the conventional method with a size of 150 nm and cubic form change into the nanoparticles with a size of 30 nm and hexagonal structure under ultrasound. The nanoparticles were mesoporous and had a specific surface area of 47.29 m2/g with improved thermal stability and superalkaline properties. The effect of the size, crystallinity, and morphology of the catalyst was examined with respect to the transesterification reaction. Calcium-strontium oxide synthesized under indirect sonication has a more uniform size and morphology than the particles synthesized by the other two methods. The efficiency of the transesterification reaction using the ultrasonic synthesized catalyst was almost double that of the catalyst synthesized by the conventional method. Calcium-strontium oxide synthesized with minimal size and high surface area was highly effective in transesterification.