Ionic covalent organic framework based electrolyte for fast-response ultra-low voltage electrochemical actuators

Area of Science:

• Materials Science
• Robotics Engineering
• Electrochemistry

Background:

• Soft actuators are crucial for soft robotics, enabling large deformations.
• Enhancing the durability and efficiency of electrochemical actuators remains a significant challenge.
• Ionic two-dimensional covalent-organic frameworks (2D COFs) offer potential for advanced actuator design.

Purpose of the Study:

• To improve the actuation performance of electrochemical actuators.
• To investigate the role of ordered pore structure in enhancing ion transport.
• To demonstrate the potential of 2D COF-based actuators for soft robotics applications.

Main Methods:

• Fabrication of an ionic 2D COF-based electrochemical actuator.
• Characterization of the actuator's performance, including displacement, response time, and frequency response.
• Evaluation of the actuator's durability over extended cycling.

Main Results:

• The 2D COF actuator exhibited a large peak-to-peak displacement of 9.3 mm at ±0.5 V and 1 Hz.
• A fast response time of approximately 1 second to reach equilibrium bending was achieved.
• The actuator demonstrated a high bending strain difference (0.38%) and broad response frequency (0.1–20 Hz).
• Excellent durability was observed, with over 99% performance maintained after 23,000 cycles.

Conclusions:

• The ordered pore structure of the 2D COF facilitates efficient ion transport, significantly improving actuator performance.
• The developed soft electrolyte-based actuator functions effectively as a bionic artificial actuator.
• This research provides insights for advancing the capabilities and applications of soft actuators in robotics.