Processing of nano to microparticulates with controlled morphology by a novel spray pyrolysis technique: A mathematical approach to understand the process mechanism

•Nano to micron size particulates of LSM synthesized with controlled morphology•Homomolecular growth of nanoparticulates carried out in-situ during the pyrolysis•Precalcined LSM nanoparticles used as the seeding agent for particle growth•Mathematical modeling based on kinetic & thermodynamic parameters & its validation•Particulate size, morphology correlated with multifaceted function as SOFC cathode

Controlling particle size and morphology during the synthesis of nanocrystalline powders by the spray pyrolysis (SP) technique is a major challenge. A mathematical modeling based on certain governing parameters is developed for predicting the critical nanocluster sizes and nanoparticulates being synthesized by two fluid SP technique. Correlation is established between experimentally obtained nanoparticulates, theoretically predicted cluster diameters and the surface areas of the synthesized powders of variable dimensions. The developed model is also proposed to apply as the standard for determining the particle sizes, cluster diameter and surface areas for any intermediate precursor concentration for a definite system. A novel method is adopted for growth of the particulates by adding precalcined powders (ash) as nucleation sites during the atomization process for the subsequent runs. Experimental validation of the model is established using strontium doped lanthanum manganite (LSM) of various particle dimensions as applicable for multi-functional purpose in solid oxide fuel cell cathode.

Graphical abstractHomogeneous-homomolecular nucleation followed by particulate growth is considered for synthesis of nano-micron size LSM particulates with tailored morphology by a novel spray pyrolysis. Seeding of precalcined ashes as nucleation sites for in-situ particulate growth is attempted. A mathematical model is developed & validated for predicting cluster diameters & surface area of LSM with tailored morphology for multifunctional application in SOFC.Figure optionsDownload full-size imageDownload as PowerPoint slide