The strong yet reversible and very pH-dependent catechol-Fe3+ coordination bonds was found in many natural substances and living beings, and has been correlated to the amazing properties (high hardness, high extensibility, strong adhesion under wet condition, and self-healing) of the cuticle of mussel byssal threads. Inspired by these phenomenon, catechol-Fe3+ structures have been frequently utilized to toughen elastomers and construct novel materials such as hard flexible coatings, under-water adhesives, self-healing polymers. In addition to the dynamic properties, catechol-Fe3+ coordination complexes also show intense and broad absorptions due to the ligand-to-metal charge-transfer (LMCT) process. The photothermal effect of catechol-Fe3+ coordination crosslinked polymer due to the broadband absorption in the ultraviolet and near-infrared regions has been wildly reported in photothermal ablation for cancer therapy and wound healing. We envisage that photothermal effect of catechol-Fe3+ coordination structure would be desirable for light driven actuators. Moreover, Fe3+-catechol coordination bonds as dynamic crosslinking sites will endow enhanced strength, adjustable viscoelastic property and self-healing property of the resulting polymer, thus can prevent the actuators from damaging and prolong their service time. Above all, introducing Fe3+-catechol coordination bonds into the photo responsive device will give it unprecedented advantages. Herein, we designed a self-healing and easily processable light-driven actuator using an iron-catechol coordination crosslinked polymer. The arrow-shaped swimming device has quite fast translation and rotation speeds. Furthermore, a light-driven ship assembled from bis-catechol-Fe3+ crosslinked polymer and sponge paper was well-designed based on the excellent photothermal property and facile fabrication of the bis-complex. The ship not only can achieve remote light-controlled versatile motion but also realize the leap from micro-scale to macro-scale of swimming devices at water/air interface. Moreover, the ship can achieve movement across obstacles and realize smart transportation and contactless delivery with the assistance of light-driven robotic arms. In this work, the concept of designing macro-scale light-driven self-propelled devices assembled from high-efficiency photothermal materials and lightweight materials paves a new way for broadening the application of swimming devices.

Catechol-Fe3+ coordination crosslinked polymer enables swimming devices for versatile motions and smart transportation

Where thousands of chemistry professionals meet to share ideas and advance scientific and technical knowledge. Spring 2023 abstracts, posters, and presentations will launch at the end of March.

ACS Spring 2023

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.