Growth and optical characterization of colloidal CdTe nanoparticles capped by a bifunctional molecule

Thiol-capped CdTe nanoparticles were synthesized in aqueous solution by wet chemical route. CdTe nanoparticles with bifunctional molecule mercaptoacetic acid as a stabilizer were synthesized at pH≈11.2 and using potassium tellurite as tellurium source. The effect of refluxing time on the preparation of these samples was measured using UV–vis absorption and photoluminescence analysis. By increasing the refluxing time the UV–vis absorption and photoluminescence results show that the band edge emission is redshifted. The synthesized thiol-capped CdTe were characterized with FT-IR, TEM and TG-DTA. The particle size was calculated by the effective mass approximation (EMA). The role of precursors, their composition, pH and reaction procedure on the development of nanoparticles are analyzed.