Molecular Metallocorrole–Nanorod Photocatalytic System for Sustainable Hydrogen Production

Abstract

Solar-driven photocatalytic generation of hydrogen from water is a potential source of clean and renewable fuel. Yet systems that are sufficiently stable and efficient for practical use have not been realized. Here, nanorod photocatalysts that have proven record activity for the water reduction half reaction were successfully combined with molecular metallocorroles suitable for catalyzing the accompanying oxidation reactions. Utilization of OH À / * OH redox species as charge transfer shuttle between freely mixed metallocorroles and rods resulted in quantum efficiency that peaked as high as 17 % for hydrogen production from water in the absence of sacrificial hole scavengers. While typically each sacrificial scavenger is able to extract but a single hole, here the molecular metallocorrole catalysts were found to successfully handle nearly 300,000 holes during their lifespan. The implications of the new system on the prospects of realizing practical overall water splitting and direct solar-to-fuel energy conversion were discussed.

Molecular Geometry and Electronic Structure of Copper Corroles

“…Corrole complexes, or metallocorroles, have been synthesized with a wide variety of transition metals and are of interest for their ability to catalyze hydrogen evolution reactions, [10][11][12][13][14][15] oxygen evolution reactions, 16,17 and oxygen reduction reactions. [18][19][20][21] Metallocorroles also have diverse applications in other areas of molecular catalysis, [22][23][24][25][26] small molecule sens-ing, [27][28][29] and in medicinal applications. [30][31][32] In addition to the highly functionalized hang-man corroles designed to play a more specialized role in catalysis, [33][34][35] substituting metallocorroles in the meso and β positions can significantly alter their reactivities.…”