A non-vacuum chemical process for rapid synthesis of nanostructured czts powders for solar photovoltaic applications

摘要

A non-vacuum chemical process for rapid synthesis of nanostructured CZTS powders for solar photovoltaic applications. The invention describes a non-vacuum aqueous-based chemical process for synthesizing nano-structured CZTS [Di - Copper Zinc Tin Tetra - Sulphide, {Cu2(Zn,Sn)S4] powders for solar photovoltaic applications. By following the process, a variety of CZTS material with variable levels of zinc and tin atomic ratio in the CZTS compound can rapidly be prepared. The synthesized CZTS powders have tetragonal kesterite structure with specific surface area in the range of 70 + 5 m2/g. Heat treatment (annealing) of the CZTS powder in any inert atmosphere, e.g., argon or nitrogen at a temperature in the range of 100 - 300°C improves the crystallinity of CZTS powder since as-synthesized CZTS powders are poorly crystalline. Electron microscopy analyses (TEM & Fe-SEM) of the CZTS powder show the nanostructure in the material with primary particles in the range of 10 - 50 nanometers and is suitable for photovoltaic applications for forming light absorption layer either by coating or printing the CZTS material following any standard procedure.