Framework Linkage Chemistry Regulates Excited‐State Chiral Photophysics in Porous Polymers for Programmable Circularly Polarized Luminescence

ABSTRACT

Developing high‐performance circularly polarized luminescence materials requires precise control over excited‐state chiral photophysics, including energy dissipation, host‐guest coupling, and chirality transfer. Chiral porous frameworks are particularly attractive material platforms because their confined nanoenvironments enable the integration of molecular recognition, energy transfer, and chiroptical modulation within a single architecture. However, the role of bond engineering in regulating their excited‐state chiral photophysics remains poorly understood. Here we develop amide‐linked chiral porous polymer nanospheres via imine‐to‐amide conversion within a BINDBA‐derived framework. These amide linkages simultaneously enhance framework rigidity, offer hydrogen‐bonding sites for guest binding, stabilize chiral nanochannels, and facilitate host‐to‐guest Förster resonance energy transfer (FRET). This structural conversion boosts the photoluminescence quantum yield by nearly 8.1‐fold and preserves the characteristic mirror‐image CPL. Utilizing nanospheres as an energy donor, the CPL is successfully extended from visible to the near‐infrared region with a dissymmetry factor reaching 0.2. Furthermore, these nanospheres can assemble into macroscopic microparticles with controllable sizes while retaining their intrinsic optical and chiral properties. This work demonstrates that bond engineering provides an effective molecular strategy for regulating excited‐state chiral photophysics in porous materials, offering a versatile platform for programmable circularly polarized luminescence and hierarchical chiral photonic architectures.