Supramolecular squares of Sn(iv)porphyrins with Re(i)-corners for the fabrication of self-assembled nanostructures performing photocatalytic degradation of Eriochrome Black T dye

Abstract

Two Sn(IV)porphyrin-based supramolecular squares (1 and 2) were synthesized via the reaction of Re(CO)₅Cl with two [trans-bis(4-pyridyl)(porphyrinato)]Sn(IV) complexes (SnP¹ and SnP²). Although the structural framework of these architectures was fixed with a closed 2D tetrameric array, altering the substituent on the Sn(IV)porphyrin units not only produced conformationally different forms but also led to distinctly different nanostructures. These nanostructured materials efficiently performed photocatalytic degradation of Eriochrome Black T (EBT) dye, thereby exhibiting degradation efficiencies between 88 and 95% within 90 min in aqueous media under the irradiation of visible-light. It was also found that the pseudo-first-order degradation rate constant of 2 was higher than that of 1.