Abstract
Using an energy source to drive chemical reactions away from equilibrium is essential for life and remains a significant challenge in designing artificial out-of-equilibrium nanosystems and molecular machines. Achieving autonomous operation of such systems, as observed in nature, presents an even greater difficulty. Here, we report Pd(II)-mediated coordination capsules based on ligand 1 embedding an azobispyrazole photoswitch. The more thermodynamically stable E-photoisomer forms an equilibrium mixture of a Pd(II)(3)(E-1)(6) double-walled triangle and a Pd(II)(2)(E-1)(4) lantern in a 78 : 22 ratio. UV-light irradiation transforms both structures into a Pd(II)(2)(Z-1)(4) lantern, which then reverts solely to the out-of-equilibrium Pd(II)(2)(E-1)(4) lantern when exposed to visible light. The complete photoisomerisation proceeds through an information ratchet mechanism that can operate autonomously under continuous white light or sunlight exposure, selectively accumulating the out-of-equilibrium Pd(II)(2)(E-1)(4) structure. This work demonstrates how autonomous, light-driven processes can be harnessed to direct non-equilibrium behaviour in complex coordination assemblies.