2025/12/19 by Anastasia Kultaeva, Anastasiia Kultaeva, Volodymyr Vasylkovskyi +13 · 1 voice
Chemistry · Energy · Materials Science · Physics and Astronomy · #Advanced Photocatalysis Techniques #Applied Physics (physics.app-ph) #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Metal-Organic Frameworks: Synthesis and Applications #Polyoxometalates: Synthesis and Applications #cond-mat.mtrl-sci #physics.app-ph #physics.chem-ph
paper · pdf · doi:10.48550/arxiv.2512.17778
published as Materials Horizons 13, 5465-5472 (2026)
arxiv created 2025/12/19 · openalex publication_date 2025/12/19 · arxiv published 2025/12/19 · arxiv updated 2025/12/19 · openalex created_date 2025/12/23 · openalex updated_date 2026/07/28
Donor-π-acceptor (D-π-A) functionalization of MOF linkers can enhance visible-light photocatalytic activity, yet the mechanisms responsible for these effects remain unclear. Here we combine EPR spectroscopy, transient photoluminescence, and first-principles calculations to examine how diazo-coupled anisole, diphenylamine (DPA), and N,N-dimethylaniline (NNDMA) groups modify the photophysics of UiO-66-NH2. All donor units introduce new occupied states near the valence-band edge, enabling charge separation through dye-to-framework electron transfer. Among them, the anisole-modified material stands out for facilitating efficient intersystem crossing into a triplet charge-transfer configuration that suppresses fast recombination and yields long-lived charge carriers detectable by photo-EPR. Meanwhile, bulkier donors such as DPA and NNDMA - despite their stronger electron-donating character - also tend to introduce defect-associated trap states. These results underscore the interplay between donor-induced electronic-structure changes, triplet pathways, and defect-mediated recombination, offering a mechanistic basis for tuning photocatalytic response in D-π-A-modified MOFs.