Efficient heterogeneous photosensitizing materials require both large accessible surface areas and excitons of suitable energies and with well‐defined spin structures. Confinement of the tetracationic cyclophane (ExBox4+) within a nonporous anionic polystyrene sulfonate (PSS) matrix leads to a surface area increase of up to 225 m2g−1in ExBox•PSS. Efficient intersystem crossing is achieved by combining the spin‐orbit coupling associated to Br heavy atoms in 1,3,5,8‐tetrabromopyrene (TBP), and the photoinduced electron transfer in a TBP⊂ExBox4+supramolecular dyad. The TBP⊂ExBox4+complex displays a charge transfer band at 450 nm and an exciplex emission at 520 nm, indicating the formation of new mixed‐electronic states. The lowest triplet state (T1, 1.89 eV) is localized on the TBP and is close in energy with the charge separated state (CT, 2.14 eV). The homogeneous and heterogeneous photocatalytic activities of the TBP⊂ExBox4+, for the elimination of a sulfur mustard simulant, has proved to be significantly more efficient than TBP and ExBox+4, confirming the importance of the newly formed excited‐state manifold in TBP⊂ExBox4+for the population of the low‐lying T1state. The high stability, facile preparation, and high performance of the TBP⊂ExBox•PSS nanocomposites augur well for the future development of new supramolecular heterogeneous photosensitizers using host–guest chemistry.
Although sonodynamic therapy (SDT) has shown promise for cancer treatment, the lack of efficient sonosensitizers (SSs) has limited the clinical application of SDT. Here, a new strategy is reported for designing efficient nano‐sonosensitizers based on 2D nanoscale metal–organic layers (MOLs). Composed of Hf‐oxo secondary building units (SBUs) and iridium‐based linkers, the MOL is anchored with 5,10,15,20‐tetra(
- Award ID(s):
- 2011854
- PAR ID:
- 10403305
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 35
- Issue:
- 19
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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