Improving the thermoelectric performance of hydrothermally synthesized FeS2 nanoparticles by post sulfurization

In this manuscript, we have synthesized the FeS2 nanoparticles by a simple hydrothermal method. Post sulfurization of the synthesized nanoparticles for different time durations (30, 60, 90 & 120 min) was performed to obtain quality samples. XRD data exhibits the phase development of FeS2 particles while some secondary phases related to FeS were also observed. Raman spectroscopy data confirm the formation of pyrite FeS2. Seebeck data suggested an improvement in Seebeck coefficient value from 44 to 88 μV/°C as the sulfurization duration was increased from 30 to 120 min. A similar increasing trend was also observed for the electrical conductivity values. This kind of improvement in the Seebeck coefficient and electrical conductivity was related to the improvement in the FeS2 pyrite phase. This improvement in crystal structure resulted in the improvement of the mobility of the carriers which leads to a high power factor value up to 3.8 × 10−5Wm−1K−2.