Synthesis and characterization of Cu₂ZnSnS₄ nanoparticles Available to Purchase

Copper zinc tin sulfide (Cu₂ZnSnS₄ or CZTS) is a p-type semiconducting material with high absorption coefficient (10⁴ cm⁻¹) and a band gap of ~1·5 eV. Most of its constituents are earth abundant and are environmentally benign. Therefore, in this work, the authors investigated structural and optical properties of CZTS nanoparticles synthesized by solvothermal method (water (H₂O), ethylene glycol (EG)). X-ray diffraction and Raman studies revealed that the CZTS nanoparticles exhibited kesterite structure with preferential orientation along the (112) direction. The crystallite sizes of the nanoparticles were found to vary from 14 nm (water) to 7 nm (EG). Morphological analysis using field emission scanning electron microscope shows that the growth of the particles is controlled using EG as a solvent. It was observed from energy-dispersive X-ray analysis spectra that the composition of the nanoparticles prepared in EG was found to be nearly stoichiometric. The calculated optical band gaps of CZTS nanoparticles were 1·39 and 1·53 eV for water and EG, respectively. The electrical conductivity of the samples was measured and found to be higher for the sample prepared in EG.