Molecularly Engineered Metal-Organic Framework With Synergistically Boosting Piezoelectric Polarization and Exciton Directional Separation Enables Efficient Piezo-Photocatalytic Atom Transfer Radical Polymerization.

Photoinduced atom transfer radical polymerization (ATRP) is often limited by the shallow penetration of visible light, and current strategies to address this limitation mainly focus on developing catalytic systems responsive to near-infrared (NIR) light. In contrast, ultrasound-driven polymerization offers deeper penetration but limited spatiotemporal control. To address these challenges, we pioneer the integration of piezo-photocatalysis into ATRP by developing a donor-acceptor (D-A) metal-organic framework (MOF) catalyst (B-Zr-C) via incorporating electron-acceptor N-(4'-carboxyphenyl)-1,8-naphthalimide (CPNI) into NH2-UiO-66, which enables synergistically enhanced piezoelectric polarization and exciton separation. Multiscale characterizations verify that the introduction of CPNI prolongs the charge-separated state lifetime and effectively increases the polarity of the MOF, as evidenced by significant increases in the piezoelectric coefficient d33, piezoelectric potential difference, and dipole moment. Under blue light and ultrasound, the piezo-photocatalytic copper-mediated ATRP apparent rate constant of B-Zr-C(1:1) is ∼fourfold higher than that under light alone, achieving high monomer conversion (> 90%, Đ < 1.11) in seven polar solvents and even producing ultrahigh-molecular-weight (UHMW) polymers (Mn > 1100 kg·mol-1, Đ < 1.30). The piezo-photocatalytic system retains 64% conversion through a 1.5 mm chicken-skin barrier (vs. < 10% for blue light alone), together with outstanding spatiotemporal controllability, chain-end fidelity, and reusability.