Raman study of colloidal CuZnSnS nanocrystals obtained by "green" synthesis modified by seed nanocrystals or extra cations in the solution.

The method of affordable colloidal synthesis of nanocrystalline CuZnSnS (CZTS) is developed, which is suitable for obtaining bare CZTS nanocrystals (NCs), cation substituted CZTS NCs, and CZTS-based hetero-NCs. For the hetero-NCs, the synthesized in advance NCs of another material are introduced into the reaction solution so that the formation of CZTS takes place preferably on these "seed" NCs. Raman spectroscopy is used as the primary method of structural characterization of the NCs in this work because it is very sensitive to the CZTS structure and allows to probe NCs both in solutions and films.