Wearable power sources should be stretchable to provide continuous electricity to devices. In spite of significant progress in the field of wearable electronics, the development of stretchable power sources is still challenging. In this study, we developed a high-performance stretchable thermoelectric generator using multi-dimensional nanocomposites. The thermoelectric power of the metal dichalcogenide (TMD) nanosheet-based active film was significantly enhanced by adding highly conducting single wall carbon nanotubes (one-dimensional material) bridging the multi-stacked TMD nanosheets, which improved the electrical conductivity and morphological stability of the active film, thus increasing its thermoelectric power factor (47 μW/K2 m). The wrinkles on the nanocomposite film rendered it geometrically stretchable. The wrinkled nanocomposite showed significantly improved thermoelectric properties and excellent strain resistance because of the slipping of the TMD nanosheets as a lubricant to release the strain applied to the wrinkles during stretching.

No abstract

No abstract

In the present study, phase-dependent gas sensitivities of MoS 2 chemical sensors were examined. While 1T-phase MoS 2 (1T-MoS 2 ) has shown better chemical sensitivity than has 2H-phase MoS 2 (2H-MoS 2 ), the instability of the 1T phase has been hindering applications of 1T-MoS 2 as chemical sensors. Here, the chemical sensitivity of MoS 2 locked in its 1T phase by using a ZnO phase lock was investigated. To develop MoS 2 chemical sensors locked in the 1T phase, we synthesized a multi-dimensional nanomaterial by growing ZnO nanorods onto MoS 2 nanosheets (ZnO@1T-MoS 2 ). Raman spectroscopy and x-ray photoelectron spectroscopy analyses of such phase-locked 1T-MoS 2 subjected to flash light irradiation 100 times confirmed its robustness. ZnO nanomaterials hybridized on MoS 2 nanosheets not only froze the MoS 2 at its 1T phase, but also increased the active surface area for chemical sensing. The resulting hybridized material showed better response, namely better sensitivity, to NO 2 gas exposure at room temperature than did 1T-MoS 2 and 2H-MoS 2 . This result indicated that increased surface area and heterojunction formation between MoS 2 and ZnO constitute a more promising route for improving sensitivity than using the 1T phase itself.

Developing facile methods for inducing phase transformation between metallic and semiconducting 2D transition metal dichalcogenide (TMDC) materials is crucial toward leveraging their use in cutting‐edge energy devices. Herein, 2H‐to‐1T’ phase transformations in chemically exfoliated Tungsten Disulfide (WS2) nanosheet films, triggered by antioxidants toward highly conductive 2D TMDC electrode materials, are introduced. It is found that antioxidants cause residual LiOx compounds to reduce to Li metal, subsequently inducing 1T’ phase transformations in layered WS2 nanosheets, resulting in significantly enhanced conductivity across the overall films. Both thermoelectric devices and supercapacitors are fabricated utilizing the highly conductive 1T’ phase WS2 nanosheet films as a working electrode, allowing for outstanding performance due to the increased conductivity of the WS2 nanosheet films. The method constitutes a facile approach toward the use of chemically exfoliated 1T’ TMDC nanosheets for highly efficient energy device applications.