Executive Summary : | Here PI proposes the development of solution-processed high efficiency superstrate solar cells using dual-cation substituted CZTS (Cu2ZnSnS4) thin film as absorber layer, vertically well aligned ZnO nanowire array as window layer and ZnS as buffer layer. Simple, low-cost, low-temperature and environment-friendly all-chemical methods are adopted to fabricate highly stable solar cell devices which are the requirements of modern day green energy technology policy. Fabrication and optimization of electrical and optical properties of kesterite CZTS thin film with partially substituted copper (Cu) and zinc (Zn) ion by silver (Ag) and strontium (Sr) ion respectively are the prime objectives of the proposed proposal. Partial substitution of Cu+1 ion by Ag+1 and Zn+2 ion by Sr+2 are expected to improve the electrical and optical properties of CZTS layer through better crystallinity and passivation of antisite defects leading to enhancement of solar energy conversion when used as absorber layer of solar cells. Modulation of electrical transport properties along with tuning of optical band gap with the Ag, Sr partial substitution in CZTS layer will be studied critically to make them suitable for solar cell absorber layer. Although, dual-cation substitution has attracted researchers as potential strategy to enhance the optoelectronic properties of CZTS layer in recent times, the optimization of device performance is scarce in literature. The proposed solar cell structure may open up new avenue to optimize the performance of CZTS thin film based device in stable superstrate configuration. |