Inherent internal p-n junction assisted single layered n-type iron pyrite solar cell

Abstract

The high absorption coefficient and low cost with plentiful availability make the material iron pyrite (FeS2) promising for solar cell applications. However, their efficiency in the literature is still around 2.8% due to their low VOC. The presence of an acceptor-type surface inversion layer (SIL) with a significant band gap (0.56 eV-0.72 eV) is the main cause of this low performance. A detailed study considering these two parameters is not available in the literature to relate device performance to underlying phenomena. Therefore, a comprehensive analysis of the band gap and doping variation of SIL was performed in this article to explore the efficiency potential of FeS2 solar cells. The results showed that SIL with a low bandgap is highly undesirable, and it is recommended to fabricate SIL with a higher band gap of 0.72 eV and a doping of 1019 cm−3 in the laboratory to achieve a conversion efficiency of 5.36%. It was also confirmed that FeS2-based solar cells without a SIL layer have the potential to deliver 10.3% conversion efficiency. The results reported in this study will pave the way for underestimating the workings of iron pyrite solar cells and developing highly efficient FeS2 solar cells.