Modifying phonon thermal conductivity in nanomaterials is important not only for fundamental research but also for practical applications. However, the experiments on tailoring thermal conductivity in nanoscale, especially in two-dimensional materials, are rare due to technical challenges. In this work, we demonstrate the in situ thermal conduction measurement of MoS and find that its thermal conductivity can be continuously tuned to a required value from crystalline to amorphous limits. The reduction of thermal conductivity is understood from phonon-defect scattering that decreases the phonon transmission coefficient. Beyond a threshold, a sharp drop in thermal conductivity is observed, which is believed to be due to a crystalline-amorphous transition. Our method and results provide guidance for potential applications in thermoelectrics, photoelectronics, and energy harvesting where thermal management is critical with further integration and miniaturization.

Topological materials attract enormous attention due to their unique physical properties and thermoelectric applications. ZrTe5, a semimetal material, is proposed to be a new topological material and shows interesting thickness‐dependent electrical transport properties. Here, the in‐plane thermal conductivity and power factor in exfoliated few‐layer ZrTe5 nanoribbons with different thickness measured using suspended thermal bridge method are reported. A nearly linearly thickness‐dependent thermal conductivity κ is observed where thicker nanoribbons present higher thermal conductivity in the temperature range of 100–300 K due to phonon‐boundary scattering. More interestingly, the room temperature figure of merit ZT of 140 nm‐thick ZrTe5 nanoribbon is five times higher than that in bulk ZrTe5, providing superior thermoelectric performance in thinner ZrTe5 nanoribbons and revealing the promising prospect of ZrTe5 nanoribbons as thermoelectric materials.

Thermal measurements of V2O5 nanowires suggest the vital role of interfacial thermal resistance in the heat dissipation in Li-ion batteries.