  We calculated the longitudinal acoustic phonon limited electron mobility of
14 two dimensional semiconductors with composition of MX$_2$, where M (= Mo, W,
Sn, Hf, Zr and Pt) is the transition metal, and X is S, Se and Te. We treated
the scattering matrix by deformation potential approximation. We found that out
of the 14 compounds, MoTe$_2$, HfSe$_2$ and HfTe$_2$, are promising regarding
to the possible high mobility and finite band gap. The phonon limited mobility
can be above 2500 cm$^2$V$^{-1}$s$^{-1}$ at room temperature.
