3d Printing of Octopi-Inspired Hydrogel Suckers with Underwater Adaptation for Reversible Adhesion

•Inspired with octopus, the hydrogel-based suckers with different structure features are fabricated by digital light processing 3D printing.•The proposed hydrogel sucker can effectively enhance adhesion and stability by constructing the interfacial water sealing with the overflow of internal free water.•The hydrogel suckers have good adhesion versatility to different substrates, liquid environments, and surface roughness.•The pneumatic hydrogel gripper integrated with the bioinspired suckers can efficiently capture objects under water and in air.