Solution processed synthesis of CZTS quantum dots and nanostructuredCZTS thin films for solar cell application

Abstract

Earth abundant, low cost, highly efficient photovoltaic material Cu2ZnSnS4 (CZTS) quantum dots have been synthesized by simple chemical precipitation technique. The X-ray diffraction pattern of CZTS quantum dots exhibit broad peaks which reveals that the synthesized particles have very small crystallite size and is found to be 9.1nm. The structural analysis and phase purity of quaternary material CZTS quantum dots have been studied by Raman spectroscopy. In the Raman spectra of CZTS quantum dots, A maximum intensity peak observed at 332cm-1 and this corresponds to the vibrational A1 symmetry mode of kesterite CZTS. The raman spectra did not show any evidence for the presence of secondary phases. The FESEM images shows that the constituents particles of CZTS have agglomerated and also the particles are small in size and spherical in shape. The HRTEM image showed lattice fringes corresponding to the kesterite phase of CZTS and the average crystallite size has been calculated using the HRTEM image and it was found to be 8.3nm. The elemental distribution in the CZTS quantum dots wascarried out using STEM elemental mapping and the images show the uniform distribution of all the four elements Cu, Zn, Snand S. newline