Steering rigidified nonplanar conjugation based perylene diimide supramolecular for enhancing photocatalytic activity

Abstract

π-Conjugated supramolecular with higher delocalization of electrons has attracted considerable attention in enhancing the charge transfer in photocatalysis. However, those conjugated macromolecules often possess varied rotational geometries, which will significantly deteriorate charge mobility but still inexplicitly. Herein, we reported diversified PDI polymers with intramolecular angles of 94.7°, 149.7° and 176.3° to explore the role of π-conjugated non-planar molecules. Density functional theory (DFT) calculations and experimental results show that vertical structural PDIMH has antibonding in anisotropic polarizable monomer to generate a macro-dipole, which greatly expands the built-in electric field and facilitates charge transfer and exciton dissociation. On the other hand, the vertical angle is favorable for the face-to-face overlap of the homogeneous molecules, which will create a carrier migration channel and promote carrier separation. Notably, PDIMH exhibited highly effective photocatalytic sterilization (near 100% in 2 h) and benzylamine oxidation (conversion rate up to 300 mmol g−1h−1), which is superior to other ever reported catalysts. This work provides a new interpretation for regulating molecular geometry in developing highly efficient photocatalyst to solve future sustainable issues.