Dipole Polarization Modulation by Breaking Geometric Symmetry in Conjugated Porous Polymers for Efficient Photodegradation of Antibiotics

Organic semiconductor photocatalysts typically suffer from high exciton binding energies (E_b) due to their low dielectric constants, which limit further improvement in photocatalytic efficiency. However, current strategies that rely on polar groups or ion doping struggle to balance high dielectric gain and long-term stability due to dipole disorder and complex synthesis. Herein, dipole polarization modulation is reported by breaking geometric symmetry in conjugated porous polymers (CPPs) to enhance the dielectric constant and achieve a low E_b of 57.6 meV. The low E_b enhances the separation and transport efficiency of photogenerated charge carriers. As a demonstration, these CPPs are subjected to photocatalytic antibiotic degradation, achieving an ofloxacin removal efficiency of 99.1% under ambient conditions. The results provide new insights into the rational design of porous materials with low E_b for efficient photocatalysis.