Influence of Cu/In loading ratio in grain size of the CuInS2 films for CuInS2-based solar cells

The attainment of Net Zero Emissions (NZE) by 2050 has become a globally acknowledged goal, and solar photovoltaic (PV) power generation stands out as one of the most promising approaches towards achieving the net zero CO
2
emissions objective. In this treatise, we present the fabrication and characterization of CuInS
2
thin-film solar cells, wherein the composition and structure of CuInS
2
layers were prepared through the process of sulfurization of Cu-In precursors. Another research endeavor was dedicated to examining the correlation between cell performance and CuInS
2
grain size, which is directly determined by the precursor Cu/In ratio. Our findings reveal that augmenting the precursor Cu/In ratio from 0.75 to 0.82 produced a surge in current density, escalating from 3.39 mA/cm$^{2}$ to a value surpassing 6 mA/cm$^{2}$. Furthermore, we obtained numerous measured parameters that evinced a higher precursor Cu/In ratio to possess the potential to enhance the efficiency of the solar cell. These findings hold immense significance as they suggest the viability of increased efficiency in solar cell performance.