Implantable artificial muscles are of great importance for muscle function restoration and physical augmentation but are still challenging. Herein, we report an artificial muscle by soaking-polymerization of polyaniline (PANI) inside a carbon nanotube (CNT) yarn. Working in aqueous biocompatible solutions, the yarn muscle generates a large contractile stroke of 17% and high isometric stress of 8 MPa at voltages lower than 2 V. The excellent performance can be ascribed to the large actuation volume that is enabled by the fast electrochemical redox of PANI confined in a coiled yarn structure. The actuation performance outperforms that of previously reported aqueous artificial yarn muscles. Moreover, the yarn muscle can work well and maintain excellent actuating performance in other biocompatible solutions such as normal saline and Na₂SO₄ aqueous solution, which makes the CNT/PANI yarn muscles suitable for implantable bionic applications. Finally, a biomimetic arm was fabricated to demonstrate the applications of the CNT/PANI yarn artificial muscle in implantable muscle, underwater robots, and soft exoskeletons.

Aqueous zinc battery has been regarded as one of the most promising energy storage systems due to its low cost and environmental benignity. However, the safety concern on Zn anodes caused by uncontrolled Zn dendrite growth in aqueous electrolyte hinders their application. Herein, sucrose with multi-hydroxyl groups has been introduced into aqueous electrolyte to modify Zn²⁺ solvation environment and create a protection layer on Zn anode, thus effectively retarding the growth of zinc dendrites. Atomistic simulations and experiments confirm that sucrose molecules can enter into the solvation sheath of Zn²⁺, and the as-formed unique solvation structure enhances the mobility of Zn²⁺. Such fast Zn²⁺ kinetics in sucrose-modified electrolyte can successfully suppress the dendrite growth. With this sucrose-modified aqueous electrolyte, Zn/Zn symmetric cells present more stable cycle performance than those using pure aqueous electrolyte; Zn/C cells also deliver an impressive higher energy density of 129.7 Wh·kg⁻¹ and improved stability, suggesting a great potential application of sucrose-modified electrolytes for future Zn batteries.