A Full-Spectrum Porphyrin-Fullerene D-A Supramolecular Photocatalyst with Giant Built-In Electric Field for Efficient Hydrogen Production

Adv Mater. 2021 Aug;33(31):e2101026. doi: 10.1002/adma.202101026. Epub 2021 Jul 8.

Abstract

A full-spectrum (300-850 nm) responsive donor-acceptor (D-A) supramolecular photocatalyst tetraphenylporphinesulfonate/fullerene (TPPS/C60 ) is successfully constructed. The theoretical spectral efficiency of TPPS/C60 is as high as 70%, offering the possibility of full-solar-spectrum light harvesting. The TPPS/C60 performs a highly efficient photocatalytic H2 evolution rate of 276.55 µmol h-1 (34.57 mmol g-1 h-1 ), surpassing many reported organic photocatalysts. The D-A structure effectively promotes electron transfer from TPPS to C60 , which is beneficial to the photocatalytic reaction. Specifically, a giant internal electric field in the D-A structure is built via the enhanced molecular dipole, which dramatically promotes the charge separation (CS) efficiency by 2.35 times. Transient absorption spectra results show a long-lived CS state TPPS•+ -C60 •- in the D-A structure, which effectively promotes participation of photogenerated electrons in the reduction reaction. Briefly, this work provides a novel approach for designing high-performance photocatalytic materials via enhancing the interfacial electric field.

Keywords: TPPS/C 60; charge separation; donor-acceptor systems; hydrogen production; photocatalysis.