5 Photochemical Properties of Dyes in/on Layered Silicates
The photophysical features of a molecule on layered silicates are much different
compared to that in solution. For example, a large red shift in absorption spectra is
observed for porphyrin derivatives upon complex formation with saponite [23, 24,
29, 35–37]. The absorption spectra of porphyrin derivatives on the surface and
between the sheets (intercalated) are shown in Fig. 8. Surprisingly, the λ max of
MgTMPyP reaches 500 nm by complex formation with saponite [38]. Systematic
Fig. 6 Absorption spectra of SSA-p-TMPyP complex at various concentrations of p-TMPyP up to
150% vs. CEC
clay nanosheet
cationic dye
no aggregation
aggregation
Fig. 7 Size-matching effect for clay-dye complexes
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Y. Ishida and S. Takagi
The photophysical features of a molecule on layered silicates are much different
compared to that in solution. For example, a large red shift in absorption spectra is
observed for porphyrin derivatives upon complex formation with saponite [23, 24,
29, 35–37]. The absorption spectra of porphyrin derivatives on the surface and
between the sheets (intercalated) are shown in Fig. 8. Surprisingly, the λ max of
MgTMPyP reaches 500 nm by complex formation with saponite [38]. Systematic
Fig. 6 Absorption spectra of SSA-p-TMPyP complex at various concentrations of p-TMPyP up to
150% vs. CEC
clay nanosheet
cationic dye
no aggregation
aggregation
Fig. 7 Size-matching effect for clay-dye complexes
192
Y. Ishida and S. Takagi