α-type zirconium hydrogenphosphate (α-ZrP) /TiO
2nanocomposite was fabricated by the intercalation of titanium tetraisopropoxide into butylamine-intercalated α-ZrP in ethanol medium and followed by photocatalytic decomposition of organic compounds with UV irradiation. Prior to the photocatalytic decomposition, hydrothermal treatment was conducted in the temperaure range of 100-250°C. All materials were characterized by X-ray diffractometry, SEM, TG-DTA, chemical analyses, FTIR,
31P MAS NMR, UV-VIS absorption spectroscopy, and photocatalytic hydrogen evolution from an aqueous methanol solution. On the basis of the SEM observation, no significant deformation of the bulk samples occurred after hydrothermal treatment and UV-irradiation whereas delamination of host materials was caused by the intercalation of butylamine.
31P MAS NMR and FTIR revealed that no chemical bonding between TiO
2and phosphate groups of the host material. TiO
2in zirconium hydrogenphosphate could be crystallized to anatase by the hydrothermal treatment. The hydrothermal treatment was effective for the photocatalytic decomposition of organic compounds. Complete decomposition was obtained in shorter UV irradiation time by the hydrothermal treatment due to the existence of anatase phase. Hydrothermally untreated α-ZrP/TiO
2exhibited negligible photocatalytic activity due to amorphous TiO
2. The photocatalytic activity of α-ZrP/TiO
2was enhanced by the hydrothermal treatment whereas the activity was decreased with an increase in the hydrothermal temperature. α-ZrP/TiO
2hydrothermally treated at 100°C exhibited the highest photocatalytic activity and showed large blue-shift in UV absorption spectra due to the quantum-size effect.
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