Fig. 2. Example artificial photosystems showing (a) a zeolitic imidazolate framework (ZIF) composed of tetrahedrally-coordinated transition metals and imidazolate linkers. ZIFs showing high adsorption and complexation towards CO2 are combined with semiconductors with more appropriate bandgaps to generate electron–hole pairs for the photocatalytic reduction of CO2. (b) a photoelectrochemical cell producing H2 from solar energy (c) a general nanoparticle-based semiconductor for photocatalytic conversion of CO2 to CO (d) artificial leaf composed of a tandem construct to produce H2 from solar energy.
