By utilizing the density gradient and upward convection flow induced by solvent evaporation, the exfoliated graphene oxide (GO) nanosheets in aqueous solution were assembled into a hierarchically structured GO paper, by which a temperature-triggered actuator was then fabricated. When stimulated by temperature, the GO paper could bend to a large curvature. At 100 °C, the curvature could reach 0.36 mm –1 within 60 s. The mechanical properties of as-prepared actuators have also been studied. The actuator exhibited a stress of 1.4 MPa when exposed to a temperature of 80 °C and showed almost identical actuating stresses in cyclic measurements. The actuation mechanism is directly related to the loss/acquisition of the interlamellar water during temperature change. Reliable and large curvature actuation could be attributed to the unique gradient structure of the pure GO papers.
No takes yet. Share an insight, caveat, or question.
Sun et al. (2011) studied this question.