Temperature-Induced Phonon Behavior In Titanium Disulfide (Tis2) Nanosheets

A detailed study of temperature-dependent phonon properties of exfoliated titanium disulphide (TiS2) nanosheets probed by Raman spectroscopy in the 80- to 450-K temperature range is reported here. The TiS2 Raman mode (E-g, A(1g), and Sh) positions exhibit linear shift dependences; however, in contradiction to typical behavior, the Sh mode surprisingly exhibits positive first-order temperature coefficient (chi=0.0592 cm(-1)/K) with increase of the temperature. In addition, the widths of studied peaks typically increase with temperature and peak intensity ratio shows no changes proving that relative phonon population is not affected by temperature. Our findings can be useful for further analysis of phonon properties and determination of thermal conductivity of supported TiS2 thin films for advanced electronics devices.