  Biaxial strain effects on electronic structures and thermoelectric properties
of monolayer $\mathrm{PtTe_2}$ are investigated by using generalized gradient
approximation (GGA) plus spin-orbit coupling (SOC) for the electron part and
GGA for the phonon part. Calculated results show that small compressive strain
(about -3\%) can induce semiconductor-to-metal transition, which can easily be
achieved in experiment. The conduction bands convergence is observed for
unstrained $\mathrm{PtTe_2}$, which can be removed by both compressive and
tensile strains. Tensile strain can give rise to valence bands convergence by
changing the position of valence band maximum (VBM), which can induce enhanced
Seebeck coefficient, being favorable for high power factor. It is found that
tensile strain can also reduce lattice thermal conductivity, which at the
strain of 4\% can decrease by about 19\% compared to unstrained one at room
temperature. By considering tensile strain effects on $ZT_e$ and lattice
thermal conductivity, tensile strain indeed can improve p-type efficiency of
thermoelectric conversion. Our results demonstrate the potential of strain
engineering in $\mathrm{PtTe_2}$ for applications in electronics and
thermoelectricity.
