Several natural organism can change shape under external stimuli. These natural phenomena have inspired a vast amount of research on exploration and implementation of reconfigurable shape transformation. The Janus structure is a promising approach to achieve shape transformation based on its heterogeneous chemical or physical properties on opposite sides. However, the heterogeneity is generally realized by multi-step processing, different materials, and/or different processing parameters. Here, we present a simple and flexible method of producing pH-sensitive Janus microactuators from a single material, using the same laser printing parameters. These microactuators exhibit reversible structural deformations with large bending angles of ∼31 and fast response (∼0.2 s) by changing the pH value of the aqueous environment. Benefited from the high flexibility of the laser printing technique and the spatial arrangements, pillar heights, and bending directions of microactuators are readily controlled, enabling a variety of switchable ordered patterns and complex petal-like structures on flat surfaces and inside microchannels. Finally, we explore the potential applications of this method in information encryption/decryption and microtarget capturing.

几种天然生物可以在外部刺激下改变形状。这些自然现象激发了有关可重构形状变换的探索和实现的大量研究。Janus结构是一种有前途的方法，该方法基于其相对两侧的异质化学或物理特性来实现形状转换。然而，异质性通常通过多步骤处理，不同的材料和/或不同的处理参数来实现。在这里，我们介绍了一种简单灵活的方法，可以使用相同的激光打印参数从单一材料生产pH敏感的Janus微执行器。这些微驱动器通过改变水环境的pH值，具有可逆的结构变形，其弯曲角约为31，响应速度快（约为0.2 s）。得益于激光打印技术的高度灵活性以及微驱动器的空间布置，柱高和弯曲方向，可以轻松控制它们，从而在平面和微通道内部实现了多种可切换的有序模式和复杂的花瓣状结构。最后，我们探索了该方法在信息加密/解密和微目标捕获中的潜在应用。