Artificial Photosynthesis

One-dimensional channel materials, such as zeolites and mesoporous silicas, are very attractive hosts for the preparation and investigation of hierarchically organized structures, presenting a successive ordering from the molecular up to macroscopic scale. The focus of this article is on artificial photonic antenna systems and on photocatalytically active layers that have been built by incorporating organic dyes, complexes, metal cations and clusters into 1-D nanochannel materials. We show that zeolite L as a host material allows for the design and preparation of a large variety of highly organized host-guest systems. The combination of a tuneable host morphology and the possibility of obtaining highly organized molecular patterns of guests leads to a variety of potential optical and photoelectronic applications. Strongly absorbing systems exhibiting efficient FRET along the c-axis of the zeolite crystals are accessible by sequential inclusion of multiple types of dyes. These new light-harvesting materials offer unique possibilities as building blocks for solar-energy conversion devices. A complementary approach consists in integrating photochemically active substances into zeolite monolayers coated on an electrode and taking advantage of intrazeolite processes for designing a reversible electrode for photocatalytic water oxidation. The photoelectrochemical water splitting capability of systems based on Ag+/AgCl/Ag-n-zeolite photoanodes are discussed.