Create a strong internal electric-field on PDI photocatalysts for boosting phenols degradation via preferentially exposing π-conjugated planes up to 100%

Nearly 100% exposure of π-conjugated planes, whose structure inherently exhibits large electron delocalization and fast charge transfer, has been achieved in perylene diimide (PDI) supramolecular photocatalysts by a solvent-induced self-assembly method. The high exposure ratio of π-conjugated planes is found to cause a larger surface potential and higher surface charge density by experimental data, and higher electron distribution by DFT calculations, relative to π-stacked planes exposed on PDI nanorods or (020) planes exposed on PDI particles, resulting in a strong internal electric field. This gives π-conjugated PDI ca. 8–17 times higher activity on phenols photodegradation than reported PDI, and 4–6 times higher activity than well-known photocatalysts like Bi2WO6 or g-C3N4. The successful control of PDI to preferentially expose π-conjugated planes may not only boost the photocatalytic activity in this system, but also give some guidelines in the design and development of more efficient organic photocatalysts with wide spectrum response.