Fast light-driven motion of polydopamine nanomembranes

Research article reporting a fast light-to-motion conversion in few-nanometer thick bare polydopamine (PDA) membranes stimulated by visible light [Nano Lett. 2022, 22, 2, 578–585]. Light-induced heating of PDA leads to desorption of water molecules and contractionn of membranes in less than 140 μs. Switching off light leads to a spontaneous expansion in less than 20 ms due to heat dissipation and water adsorption. This work demonstrates that pristine PDA membranes are multi-responsive materials, and paves the way for their use as robust building blocks for soft, micro, and nanoscale actuators stimulated by light, temperature, and moisture level.