Integrating electron donor and acceptor chromophores as ligands within one MOF for light harvesting and photocatalysis appears to be a major synthesis challenge. Meanwhile, high-efficiency and selective aerobic oxidative coupling of amines to imines under mild conditions is highly desirable for scientific and industrial fields. Herein, via a facile onepot synthetic strategy, an electron donor porphyrin ligand 5,15-di(pbenzoato)porphyrin (H 2 DPBP) was successfully integrated into a naphthalene diimide (electron acceptor)-based Zr-MOF (Zr-NDI) to construct a mixed-ligand MOF (Zr-NDI-H 2 DPBP) benefiting from the two ligands with similar geometry and connectivity. When utilized as a heterogeneous photocatalyst for aerobic oxidative coupling of benzylamine at room temperature, the prepared mixed-ligand Zr-NDI-H 2 DPBP exhibited a boosted imine generation rate (136 mmol g −1 h −1 ) far exceeding those of other noble-metal-free MOF photocatalysts and can be successfully applied to various benzylamine derivatives. Furthermore, from the results of the experiments and density functional theory calculations, the photocatalytic performance of Zr-NDI-H 2 DPBP is attributed to the photoinduced electron transfer from the donor H 2 DPBP to the acceptor NDI and the energy transfer facilitated by the photosensitized H 2 DPBP under irradiation, which effectively improve the electron−hole separation efficiency to generate abundant reactive active species of superoxide radical (O 2•− ) and singlet oxygen ( 1 O 2 ), respectively. This work provides an avenue to construct electron donor and acceptor chromophore-based light-harvesting systems by utilizing mixed-ligand MOFs as platforms to boost the solar-energy conversion.

Cerium (IV)-based metal-organic frameworks (MOFs) are highly desirable due to their unique potential in fields such as redox catalysis and photocatalysis. However, due to the high reduction potential of Ce IV species in solution, it is still a great challenge to synthesize Ce IV -MOFs with novel structures, which are extremely dominated by the hexanuclear CeÀ O cluster inorganic building units (IBUs). Herein, a CeÀ O IBU chain containing Ce IV -MOF, CSUST-3 (CSUST: Changsha University of Science and Technology), was successfully prepared using the kinetic stabilization study of UiO-66(Ce)-NDC (H 2 NDC = 2,6naphthalenedicarboxylic acid). Furthermore, owing to the superior redox activity, Lewis acidity and semiconductor-like behavior owing to Ce 4 + , activated CSUST-3 was demonstrated to be an excellent catalyst for CO 2 chemical fixation. One-pot synthesis of styrene carbonate from styrene and CO 2 was achieved under mild conditions (1 atm CO 2 , 80 °C, and solvent free). Moreover, activated CSUST-3 was shown to be a remarkable co-catalyst-free photocatalyst for overall water splitting (OWS), rendering 59 μmol g À 1 h À 1 of H 2 and 22 μmol g À 1 h À 1 of O 2 under simulated sunlight irradiation (Na 2 S-Na 2 SO 3 as sacrificial agent).

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