Typical Synthesis and Environmental Application of Novel Ti Nanoparticles - Advanced Materials for Agriculture, Food and Environmental Safety - page 434

Figure 15.10 (a) TEM images of FNT1; (b) High resolution with high magnii cation
of FNT1 TEM; (c) Enlargement of one of the spheres in Fig. 15.10a and SAED pattern
of same sphere of FNT1; (d) Enlargement of one of the mesoporous spheres from
(Figure 15.10c).

been exerted to achieve highly crystallized and narrowly dispersed TiO 2
nanoparticles using the sol-gel method with other modii cations, such as
a semicontinuous reaction method by Znaidi et al. [129] and a two-stage
mixed method and a continuous reaction method by Kim et al. [130, 131].
Qiu et al. [132] found that a typical SEM image of the TiO 2 nanotube
array with the ZnO nanorod array template was synthesized by sol-gel
method. h e TiO 2 nanotubes inherit the uniform hexagonal cross-sectional
shape and the length of 1.5 nm and inner diameter of 100-120 nm of the
ZnO nanorod template. As the concentration of the TiO 2 sol is constant,
well-aligned TiO 2 nanotube arrays can only be obtained from an optimal
dip-coating cycle number in the range of 2-3 cycles. A dense, porous TiO 2
thick i lm with holes is obtained instead if the dip-coating number further
increases. h e heating rate is critical to the formation of TiO 2 nanotube
arrays. When the heating rate is extra rapid, e.g., above 6

C min -1 , the TiO 2
coat will easily crack and l ake of from the ZnO nanorods due to great
tensile stress between the TiO 2 coat and the ZnO template, and a TiO 2 i lm
with loose, porous nanostructure is obtained.
In the presence of UV light, FNT1 reduces the 4-Nitrophenol (4-NP) to
4-aminophenol using a little bit of NaBH 4 , in contrast to pure TiO 2 and other
compositions of Fe x Nb x Ti 1-2x O 2-x/2 photocatalysts [122]. h e 4-nitrophenol is

°