Experimental and computational studies of CCTS material: Novel design of solar cell for high efficiency

Abstract

This paper focuses on the performance of Cu2CoSnS4 (CCTS)-based solar cell in the context of thin film technology, which has received less attention compared to its CZTS-based counterpart. The research work aims to bridge this knowledge gap by examining the efficiency of CCTS-based cell in an eco-friendly frame. Indeed, it reports on the thermal evaporation of CCTS thin film on glass substrate and numerical simulation of a CCTS-based solar cell using SCAPS 1D software. The basic characteristics of CCTS film are studied by UV–VIS and PL techniques revealing high absorption coefficient of 104 and bandgap energy of 1.4 eV which allow it to absorb a significant portion of the solar spectrum leading to an enhanced photon-to-electricity conversion. The next step suggests the modelling of new photovoltaic structure including such material as absorber: Ag/ZnO/In2S3/CCTS/Pt. The CCTS cell shows a promising conversion efficiency of 14.76% after an overall optimization of buffer and absorber layers. The upgraded efficiency is related to the improvement of short current density to 28.824 mA/cm2 and FF to 63.6% while open-circuit voltage remains unchanged. This positive impact is originated from the reduction of barrier at buffer/absorber interface with the increasing of absorber layer affinity resulting in the fall of cliff-like conduction band offset CBO, accordingly electrons can easily reach the front contact. The obtained values are compared withhigh-efficient solar cells which will motivate the manufacture of a similar device.