
100 Producing Fuels and Fine Chemicals from Biomass Using Nanomaterials
continues until the exhaustion of sacricial agents, as shown in Figure 4.2c. In the
half reaction of water oxidation, an electron acceptor, such as silver nitrate or iron
(III) chloride, is applied to take photogenerated electrons from the conduction band
of the photocatalysts (Figure 4.2b). The water oxidization reaction takes place at the
surface of the co-catalysts, such as RuO
2
and IrO
2
, and positive holes in the valence
band of the metal oxides oxidize the water to produce oxygen under UV or visible
irradiation. The process totally depends on the band gap of the photocat ...