Distinct anisotropy and a high power factor in highly textured TiS2 ceramics via mechanical exfoliation†
Abstract
Polycrystalline bulk of TiS2 with a remarkable enhancement of the texture degree was obtained by densifying powders refined by a liquid-based mechanical exfoliation process. As compared to the pristine TiS2, the in-(a–b)-plane mobility in the exfoliation sample increased from 5.9 to 9.8 cm2 V−1 s−1 with an almost unaffected carrier concentration, in spite of the increased scattering due to grain boundaries. As a result, a tremendously high power factor of up to 16 μW cm−1 K−2 at 673 K was achieved, which is 60% higher than that of the pristine TiS2 and is the highest for bulk TiS2 at high temperatures.