Effects of incorporating pyrite-analogous CoSe2 on the thermoelectric properties of TiS2.

In this study, we delved into the thermoelectric characteristics of TiS 2 - x mol% CoSe 2 composites, with x varying from 0 to 3. The incorporation of a modest quantity of CoSe 2 prominently enhanced the grain orientation of TiS 2. Nevertheless, a subsequent increase in CoSe 2 content led to a rapid deterioration of the TiS 2 grain orientation. The electrical conductivity σ exhibited an initial surge followed by a decline upon the addition of CoSe 2. Conversely, the absolute Seebeck coefficient | S | initially decreased and then rose. Notably, the power factor PF of TiS 2 peaked at 14.4 μWcm−1K−2 upon the inclusion of 2 mol% CoSe 2 , marking a substantial 1.7-fold enhancement compared to pristine TiS 2. Furthermore, the thermal conductivity κ of TiS 2 was effectively suppressed by the addition of CoSe 2. Consequently, TiS 2 - 2 mol% CoSe 2 achieved a ZT max value of 0.59 at 673 K, representing a noteworthy 1.8-fold increase over pristine TiS 2. • The σ and S of TiS2 were improved simultaneously by CoSe2 addition, leading to a higher PF. • The κ of TiS2 was suppressed by compositing with CoSe2. • The ZTmax of TiS2 has been improved to 0.59 at 673 K. [ABSTRACT FROM AUTHOR]