Thermal Conductivity of Few-Layer PtS₂ and PtSe₂ Obtained from Optothermal Raman Spectroscopy

Two-dimensional (2D) noble transition-metal dichalcogenides (NTMDs) have drawn widespread attention due to the promising applications in electronics and optoelectronics. Here, we studied and measured the thermal transport properties of few-layer PtSe₂ and PtS₂ using an optothermal Raman technique. First, we obtained the temperature- and laser-correlative Raman spectra of PtS₂ and PtSe₂ with disparate thicknesses. It is found that with the temperature and laser power increase, the A_1g and E_g modes of all specimens show red shifts. The thermal conductivity values can be extracted from these data, which are correlated with the first-order coefficients of study on the relationship between temperature and laser power. The resulting thermal conductivities are 85.6 ± 7.70 and 40.4 ± 4.67 W/(m·K) for 4 nm PtS₂ and 4.5 nm PtSe₂ at room temperature, respectively. The results of this work help in the design of thermal management NTMD-based devices.