J. Ram Kumar

Optical properties of thiol-stabilised CdTe nanoparticles

Thiol-capped CdTe nanocrystals with cubic zinc blende structure were synthesised in aqueous solution by wet chemical route and microwave assisted method. A series of cadmium telluride (CdTe) nanoparticles capped with mercaptoacetic acid were prepared using different pH values. The synthesised nanoparticles have been characterised with Raman, FT-IR, ultraviolet visible (UV-Vis) absorption, fluorescence spectroscopy and X-ray powder diffraction (XRD) studies.

Colloidal synthesis and characterization of Cu2ZnSnS4 nanoplates

Synthesis of copper zinc tin sulphide (Cu 2 ZnSnS 4 ) with nanoplate morphology was achieved through colloidal method using oleic acid as capping agent and solvent with 1-octadecene (1-ODE) at 240℃. X-ray diffraction (XRD) analysis shows that the synthesized nanoplates possessed pure kesterite phase. SEM analysis clearly shows the formation of nanoplates having the size of about 50-100 nm. Electron spin resonance (ESR) spectrum analysis of the prepared nanoplates shows that the valence state of copper (Ⅱ) which indicates the strong coupling with other metal ions. Thermo gravimetric/differential thermal analysis (TG/DTA) analysis shows the weight loss of sample at 450℃ predicting the loss of capping ligands on the surface of the nanoparticles. The possible mechanism for the conversion of nanoplate-like structures during synthesis was discussed. The results are discussed in detail.