Efficient, broadband self-trapped white-light emission from haloplumbate-based metal-organic frameworks.

Metal-organic frameworks (MOFs) with low-dimensional, deformable haloplumbate secondary building units (SBUs) are an emerging class of intrinsic white-light emitters combining advantageous properties of both MOFs and lead perovskites. Herein, we have successfully synthesized two MOFs with haloplumbate SBUs occupying an extremely high degree of structural strain with local zigzag Pb-X-Pb-X (X = Cl/Br) connectivity located in single-stranded helices. Thus, the electron-phonon coupling in the deformable SBUs affords intrinsic white-light emission and moderately high external photoluminescence quantum efficiencies of 12-15%, superior to our previously reported MOFs. Moreover, the excellent photocarrier diffusion properties of lead perovskites have been successfully incorporated into the MOFs with high chemical robustness in moisture (up to 90% relative humidity, RH).