Azophenyl Covalent Organic Frameworks for Efficient Photothermal Conversion and UV-Driven Soft Actuators

Two-dimensional covalent organic frameworks (2D COFs) play an important role in material separation and catalysis due to their excellent performance. However, there is little research on the application of COFs in soft actuators. In this article, we successfully synthesized the first azo doped poly(COF) using a solvent thermal method and sprayed it onto the surface of a PET film for optical driving. The 2D-COF-PET film exhibits excellent photothermal properties and a fast response (<10 s), with a driving direction completely opposite to that of a single pore azo-COF. Meanwhile, we also investigated the photothermal ability and deformation effect of COFs without azo groups, indicating that the driving ability of azo-COFs is not caused by their photothermal ability.