Drosera‐Inspired Dual‐Actuating Double‐Layer Hydrogel Actuator

Abstract Drosera is a small insectivorous plant whose antennae can fold up, encircle, and prey. The rapid movement of the antennae is achieved by the synergistic effect of a double‐layer structure with the antennae contracts on the front and expands on the back. In this work, a drosera‐inspired dual‐actuating double‐layer hydrogel actuator is proposed, in which the temperature‐responsive poly(N, N‐diethyl acrylamide) (PDEAAm) layer acts as the main actuation layer and a moisture‐responsive poly(acrylamide) (PAAm) layer acts as the auxiliary actuation layer. In a water environment with low temperature, both the PAAm and PDEAAm layers absorb water and expand with a swelling property. When the temperature exceeds the lower critical solution temperature of PDEAAm, the PDEAAm layer undergoes a hydrophilic–hydrophobic transition and shrinks rapidly. Therefore, the synergistic effect of the double‐layer hydrogel enables the double‐layer hydrogel to achieve a large bending angle at high temperature. In addition, when designing and fabricating shape‐patterned double‐layer hydrogels, complex shape changes can be achieved. Due to the physical and chemical properties, the actuator can be used to grab, transport, and release objects. This drosera‐inspired double‐layer hydrogel actuator has high practical value, which may provide new insights for the design and manufacture of artificial intelligence materials.