Figure 2a,b shows typical TEM images of the products
prepared in the solution of SDS surfactant at lower and higher
magnifications. Aggregated nanorods were observed, and the
edges of almost all the nanorods were shared with other
nanorods. A unique morphology of radial-shaped needles is
recognized as shown in Figure 2a. The nanorods exhibit a
narrower average width of 22.1 nm compared with that prepared
in water. The nanorods prepared in SDS solution also have sharp
edges as shown in Figure 2b. Figure 2c presents the corresponding
SAED pattern of the nanorods shown in Figure 2b. It
is confirmed that the pattern is the [011h0] zone axis pattern of
the hexagonal closed-pack structure, and the lattice constants
of the nanorods correspond with those of the wurtzite ZnO as
in the case of the nanorods prepared in water. The diffuse streaks
appeared around the diffraction spots along the reciprocal [2h110]
and [21h1h0] directions. The directions of rod axis were parallel
to the direction of [0001], and mainly radiated outward from
the center of the radial-shaped needles.