A complementary strategy for producing moisture and alkane dual-responsive actuators based on graphene oxide and PDMS bimorph

Smart actuators that enable deforming in a predictable manner under external stimuli have revealed great potential for both traditional and emerging industries. Generally, an asymmetric bilayer structure with one layer active and the other inert to a certain stimulus is essential to realize bending behavior. However, towards the development of dual-or multi-responsive actuators, it still lacks universal and effective strategies for rational design and fabrication of such devices through the simplest way. In this paper, we report a complementary strategy to produce dual-responsive bilayer actuators by combining the moisture-active/alkane-inert graphene oxide (GO) layer with the alkane-active/moisture-inert polydimethylsiloxane (PDMS) layer. The GO@PDMS bimorph actuator can switch its active and inert layers in response to moisture and alkane, respectively, realizing dual-responsive deformation under different actuations. Typical dual-responsive actuators, including a selective air valve and a grip and hook smart claw, are successfully fabricated, demonstrating the capability of effective gases and objects transmission. The complementary bimorph actuator may hold great promise for developing intelligent devices and portable delivery systems.