The basic photocatalytic reactions can be explained with six equations (see
Fig. 9.4). The absorption of higher-energy photons versus the energy level of
photocatalyst band gap is an essential primer step. Equation 9.2: Photon absorption
leads to transfer of valence band electrons to conduction band and creation of hole
Fig. 9.2 Three ways of interaction of light with the material including reflection, scattering, and
absorption. Ex. S. and G. S. represent excitation and ground states, respectively
Fig. 9.3 Five possible main steps for interaction of light to the bulk of media and surface of the
heterogeneous photocatalyst include surface adsorption, photodegradation reactions, and desorption of conclusive products over the surface to the bulk media
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M. Chahkandi and M. Zargazi
Fig. 9.4). The absorption of higher-energy photons versus the energy level of
photocatalyst band gap is an essential primer step. Equation 9.2: Photon absorption
leads to transfer of valence band electrons to conduction band and creation of hole
Fig. 9.2 Three ways of interaction of light with the material including reflection, scattering, and
absorption. Ex. S. and G. S. represent excitation and ground states, respectively
Fig. 9.3 Five possible main steps for interaction of light to the bulk of media and surface of the
heterogeneous photocatalyst include surface adsorption, photodegradation reactions, and desorption of conclusive products over the surface to the bulk media
288
M. Chahkandi and M. Zargazi