Ligand-regulated photoinduced electron transfer within metal–organic frameworks for efficient photocatalysis

Abstract

Dye-based metal–organic frameworks (MOFs) have received great attention due to their excellent photochemical stability in photocatalysis. However, the control of photoinduced electron transfer (PET) from dye to substrates rather than...

Eu3+-Doped Anionic Zinc-Based Organic Framework Ratio Fluorescence Sensing Platform: Supersensitive Visual Identification of Prescription Drugs

“…Photoinduced electron transfer (PET) is a wellrecognized quenching mechanism for drug molecules in MOFs, which involves not only the overlap of absorption and excitation bands between donors and acceptors but also the transfer of electrons from the lowest unoccupied molecular orbital (LUMO) orbits of MOFs to the LUMO orbits of the analyzed drug molecules. 44,61 In the case where the LUMO orbital of the MOF is at a higher energy level than the LUMO orbital of the drug molecule, electrons are transferred from the ligand to the drug molecule, which leads to quenching of the fluorescence of the MOF donor (the lower the energy level of the LUMO orbital of the target analyte, the more effective the fluorescence quenching). 62,63 As shown in Figures 6b and S25, compared to the orbital energy levels of most other prescription drugs, DEM has a lower LUMO energy level.…”

Reticular framework materials for photocatalytic organic reactions

“…Inspired by molecular chromophores, there are plenty of choices for the design of organic ligands with photosensitive property, such as acridine and other N- or S-containing heterocyclic compounds. 258 Based on their light absorption, the electron-donating or electron-accepting abilities of ligands enable fast electron transfer and greatly promote the electron–hole separation efficiency. Moreover, the Lewis basic sites in organic moieties can provide anchor points on the porous surface of MOFs for substrate binding, also enhancing the reaction activity and selectivity.…”

Proton-induced switching of excitation-wavelength-dependent emission based on mixed-ligand metal–organic frameworks

“…42–44 Meanwhile, the flexible composition ratio of ML-MOFs permits the simultaneous existence of the ligand-to-ligand energy-transfer (ET) emission band and the intrinsic ligand emission band, in which the relative intensities of these two emission bands could be further modulated by controlling the excitation wavelength to generate wide-band Ex-De emission. 45–47 Furthermore, the specific functionalization of building units enables adjusting the excited states of ML-MOFs under physical/chemical stimuli, which provides the ability to modulate the luminescence properties of emission centers, making it possible to regulate the Ex-De emission behavior. 48–51 Therefore, luminescent ML-MOFs with a stimuli-responsive excited-state process might be an ideal platform for realizing controllable Ex-De emission behavior through reversible stimuli-responsive behaviors of functional groups.…”