Mesostructured Nonwovens with Supramolecular Tricycloquinazoline Nanofibers as Heterogenous Photocatalyst

Functional supramolecular nanostructures are a promising class of materials, which can be used as potential heterogeneous photocatalysts in water. Self-assembly to nanoobjects in solution typically requires large solubilizing groups linked to the photoactive building block, and possibly hampers access to the photocatalytic active sites. Herein, a straightforward method to fabricate supramolecular nanofibers based on the disclike tricycloquinazoline (TCQ) by physical vapor deposition (PVD) is reported. It is demonstrated that TCQ can be assembled on different substrates into supramolecular nanofibers with diameters of about 70 nm resulting in densely packed fiber layers. With optimized conditions, the evaporation time allows full control over the fiber length and the absorbance of the TCQ fiber layer. A bottlebrush-like morphology with TCQ nanofibers is realized using glass-microfiber nonwovens as porous support. These mesostructured nonwovens can be used as photocatalysts for the degradation of rhodamine B in a batch process in water where the morphology remains intact after the reaction. After photocatalytic degradation of rhodamine B or tetracycline under continuous flow conditions, the supramolecular TCQ nanofibers still remain on the support. These findings demonstrate that PVD is a feasible approach to achieve functional mesostructured nonwovens with controlled morphology for use and reuse in catalytic applications.