Precursor-dependent shape variation of wurtzite CdSe crystals in a microwave-assisted polyol process

Abstract

We report a unique synthetic approach to fabricate CdSe crystals with tunable morphology and optical properties via a microwave-assisted polyol process. The morphology of CdSe crystals has been controlled by adjusting the relative amounts of two cadmium precursors CdCl 2 and CdO in a polyol solvent of ethylene glycol or glycerol; spheres, pebbles, sheets, and tetrapods of CdSe wurtzite structures with their sizes ranged from nanometers to sub-micrometers have been prepared facilely under microwave irradiation. The growth mechanism is discussed in terms of the LaMer theory; the nucleation and growth kinetics of CdSe, which depends decisively on cadmium precursors and polyol solvents, determines the shapes and sizes of diverse CdSe crystals.

Manganese Trioxide with Various Morphologies: Applications in Catalytic Dye Degradation

“…The development of various morphologies for Mn 2 O 3 has been investigated by different synthetic methodologies as a function of salt concentration, pH of the medium, solvent types, templates, and reaction temperature. There are examples of precursor dependent morphology evolution in case of ZnO, CdS, Cu 2 S and CdSe . Similar studies for the manganese‐based oxides are not reported to the best of our knowledge.…”

LaMer's 1950 model of particle formation: a review and critical analysis of its classical nucleation and fluctuation theory basis, of competing models and mechanisms for phase-changes and particle formation, and then of its application to silver halide, semiconductor, metal, and metal-oxide nanoparticles

“…The authors interpret the anisotropic growth of the (CdSe) n nanocrystals using the 1950 model in a qualitative discussion and using two different curves (Fig. 8c of that paper 131 ), one with a short time-span in the nucleation stage for the low solubility CdO precursor and one with a long time-span in the nucleation stage for CdCl 2 , which is highly…”

Facile synthesis of composition-gradient Cd1−xZnxS quantum dots by cation exchange for controlled optical properties

“…The controlled fabrication, characterization, and application of nanoscale materials have been studied widely due to their functional properties. [1][2][3][4] Colloidal semiconductor nanocrystals, also called ''quantum dots'' (QDs), are middle-stage materials, which are between atoms or molecules having discontinuous electronic-energy levels and bulk materials having continuous electronic-energy bands. Thus, the study of nanocrystals has been one of the most important subjects about the fundamental understanding of nanosized materials as well as the successful application of nanoparticles.…”