Bubble‐Assisted Dynamic Confinement Enables Programmable Solid‐State Photoswitching and Heterogeneous Photoresponsive Architectures

ABSTRACT

Achieving programmable photoisomerization of azobenzenes in the solid‐state remains a long‐standing challenge for photoresponsive materials. Here, we introduce a dynamic soft‐confinement strategy using bubble‐assisted assembly to manipulate molecular aggregation via tunable surface energy at the solid‐liquid interface. By controlling the morphologies of microfluidic channels (necktie‐like, strip‐like, and necklace‐like), we achieve distinct self‐assembled aggregates of microcubes, corded scaffolds, and microplates, with tailored freedom of the photoswitchable molecule. The strip‐like channel, formed by thinning bubble walls, traps metastable intermediates, yielding a corded scaffold structure with favorable light penetration, weaker intermolecular interactions, and loosened molecular packing for isomerization. This design achieves near‐quantitative bidirectional E ⇆ Z photoisomerization (96%–98%) in the solid‐state, rivaling solution‐like performance. Multi‐scale characterization and computational analyses reveal the critical role of confined aggregation kinetics in controlling molecular motion. Furthermore, heterogeneous patterning demonstrates programmable photoresponsive arrays for photomechanical applications. This strategy provides a scalable platform for dynamically controlling supramolecular self‐assembly pathways and designing solid‐state photoresponsive materials with programmable functions.