Dramatically enhanced thermoelectric performance of MoS₂ by introducing MoO₂ nanoinclusions

Abstract

Adopting an oxygen doping strategy, the thermoelectric efficiency of MoS2 can be enhanced up to 50 times with the best performance appearing along the cross-plane direction.

High‐temperature electrical and thermal transport behaviors in layered structure WSe2

“…The positive Seebeck coefficient indicates a p-type electrical transport behavior. 23,31,32 Figure 5 presents the temperature-dependent thermoelectric properties of WSe 2 sintered at 1123 K perpendicular (in-plane) and parallel (out-of-plane) to the pressing T A B L E 1 Temperature dependence of electrical conductivity, Seebeck coefficient of WSe 2 disk samples with thickness of 3 mm sintered at direction. [49][50][51][52] It can be seen that the results of three times (Table 1) are almost accordant, indicating that our results are repeatable.…”

“…Nevertheless, the value is still drastically higher than that of other investigated TMDCs. 23,31,32 Figure 5 presents the temperature-dependent thermoelectric properties of WSe 2 sintered at 1123 K perpendicular (in-plane) and parallel (out-of-plane) to the pressing direction. The sample exhibits anisotropic electrical conductivity and Seebeck coefficient.…”

“…22 Hence, it can be predicted that WSe 2 would be a better thermoelectric material than TiS 2 and MoS 2 . 23,31 It can be predicted that the performance of WSe 2 would be enhanced with optimization of synthetic process and chemical doping, and it will prove to be a promising thermoelectric material. Their results indicate that p-type WSe 2 is a really ideal thermoelectric material.…”

“…Transition-metal dichalcogenides semiconductors (TMDCs) are stacked structures with strong covalent bonding between metal and chalcogen, and weak van der Waals interactions between adjacent layers of the MX 2 (M=Ti, Zr, Mo or W and X=S or Se) ( Figure 1A), holding great potential as environment-friendly thermoelectric materials. [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] Disulfides (e.g., TiS 2 and MoS 2 ) are widely researched as thermoelectric materials in recent experiments. 23,24,27,[33][34][35][36] However, the thermal conductivity of these materials are so high (usually over 5 Wm À1 K À1 at room temperature), 23,[33][34][35][38][39][40] that the ZT value is dramatically limited.…”

“…The maximum ZT value reaches 0.03 at 923 K, which is significantly larger than that of pure disulfides. 23,31 It can be predicted that the performance of WSe 2 would be enhanced with optimization of synthetic process and chemical doping, and it will prove to be a promising thermoelectric material.…”