Temperature dependent phononic response of liquid phase exfoliated few layered WS2 nanosheets

We studied the temperature dependent phononic response of few layered liquid phase exfoliated WS2 nanosheets using Raman spectroscopy. Our temperature dependent Raman spectroscopy results shows that the E12g (in-plane) and A1g (out-of plane) modes in WS2 follow a systematic red shift and exhibits linear temperature dependence in the temperature range of 80 to 600 K. The temperature dependencies of the phonon modes are well described by considering the effect of S vacancies in the lattice and subsequent decrease of interlayer coupling in the adjacent WS2 layers with increase in temperature.