Thermally activated memristors from solution-processed two-dimensional (2D) semiconductors, fabricating methods and applications of the same. The memristor includes a semiconductor film formed on a nanoporous membrane, and at least two electrodes spatial-apart formed on the semiconductor film and electrically coupled with the semiconductor film to define a channel in the semiconductor film between the at least two electrodes, where the channel has one or more filaments, one or more dendrite, or a combination of them formed in the semiconductor film. The underlying switching mechanism applies generally to a range of 2D semiconductors including, but not limited to, MoS2, MoSe2, WS2, ReS2, InSe, or related 2D semiconductor materials.