Interfacial analysis and reaction engineering of sucrose ester mediated solution spray synthesis of lead chromate nanorods

Abstract

Present paper reports coconut fatty acid-sucrose ester mediated coprecipitation synthesis of lead chromate nanocrystals with monoclinic symmetry in the size range of 18–48nm. Solution spray reactor used for conducting the reactive crystallisation provides falling film mode of contact between atomised reactants. The adsorption density, surface functional groups, lattice parameters, size, morphology and optical properties of the PbCrO4 nanorods were determined by their surface tension, FTIR, XRD, FESEM-EDX and UV–vis analysis, respectively. The concentration and thus surface-active properties of sucrose ester were found to influence the crystallographic parameters, aspect ratio and UV–vis absorption properties of PbCrO4 nanocrystals. The nucleation parameters—induction time and energy barrier were reduced by 72% with increase in surfactant loading from 2 to 10g/L for given initial supersaturation—200,000 and reaction temperature—303K. The inter-multilayer and -micelle reactant exchange mechanisms were proposed and established to interpret the role of surfactant aggregation in enforcing the size stabilization, phase uniformity and polymorph selectivity in reference to kinetics and thermodynamics of precipitation of PbCrO4. The investigations are expected to fulfill the growing demand of developing appropriate theoretical principles and modelling methodologies in relation to the rationale control of size, polydispersity and structure of nanopigments.