A novel crystal-growth system and morphology control
of ZnO are
achieved by using cetyltrimethylammonium chloride (CTAC), a general
surfactant, in a new role. We synthesize ZnO via the layered hydroxide
zinc acetate (LHZA) in ethanolic-aqueous zinc acetate solution. The
CTAC surfactant plays three roles in the nucleation and crystal growth.
First, it suppresses the formation of a strong concentration gradient
in the solution. Second, it reduces the rates of nucleation and crystal
growth of LHZA through diffusion-rate control in the solution. Finally,
it expedites the formation of ZnO by increasing the solution pH. The
competitive reaction, controlled by CTAC, between the nucleation and
crystal growth of LHZA and the formation and crystal growth of ZnO
results in the formation of a novel ZnO morphology. This morphology
is composed of layered, nearly spherical particles, which are formed
by the stacking of nanosheets with single-crystal-like, mesoporous
structures.