Dual light control of a catalytically-driven chemical reaction cycle

Chemically-fueled chemical reaction networks (CRNs) are key in controlling dissipative self-assembly. Having catalysts gating fuel consumption for both the activation and deactivation chemistry of (assembly-prone) monomers and controlling the catalytic activity with an external stimulus would provide better control over where, when, and how long self-assembled structures can form. Here we achieve light control over two different catalysts that govern both monomer activation and assembly into supramolecular fibers, as well as deactivation and fiber disassembly. Activation proceeds via photoredox catalysis under visible light, whereas deactivation is achieved by organometallic catalysis that relies on a photocaged pre-fuel activated by ultraviolet light. Overall, we show how supramolecular fibers can be formed and destroyed using light.