Synthesis of Nanocrystalline FeS2 with Increased Band Gap for Solar Energy Harvesting

In this paper, we have reported the synthesis of FeS2 of higher band gap energy (2.75 eV) by using capping reagent and its successive application in organic-inorganic based hybrid solar cells. Hydrothermal route was adopted for preparing iron pyrite (FeS2) nanoparticles with capping reagent PEG-400. The quality of synthesized FeS2 material was confirmed by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared, thermogravimetric analyzer, and Raman study. The optical band gap energy and electro-chemical band gap energy of the synthesized FeS2 were investigated by UV-vis spectrophotometry and cyclic voltammetry. Finally band gap engineered FeS2 has been successfully used in conjunction with conjugated polymer MEHPPV for harvesting solar energy. The energy conversion efficiency was obtained as 0.064% with a fill-factor of 0.52.