Computational analysis of FeS2 material for solar cell application.

Pyrite (FeS2), an ultra-cheap material, has garnered much interest in photovoltaic applications due to its suitable bandgap and high absorption coefficient. However, low VOC values and high defect density have limited its efficiency. The high carrier density of FeS2, suboptimal conduction band offset, and interface defects are some of the issues limiting its efficiency. We here performed a computation study to discover the various avenues that could enhance the efficiency of such cost-effective and widely abundant pyrite material. The carrier density and conduction band offset optimization have improved efficiency from 0.01 to 2%. The efficiency improved considerably from 2 to 11% after the crucial Fermi level pining optimization at the FeS2/CdS interfaces. We, step by step, increased the efficiency from ~ 0.01 to 11% by diagnosing the FeS2 defect and following the remedial optimization. [ABSTRACT FROM AUTHOR]