▎ 摘　　要

The temperature dependence of the mobility in suspended graphene samples is investigated. In clean samples, flexural phonons become the leading scattering mechanism at temperature T greater than or similar to 10 K, and the resistivity increases quadratically with T. Flexural phonons limit the intrinsic mobility down to a few m(2)/Vs at room T. Their effect can be eliminated by applying strain or placing graphene on a substrate.