The ZnO nanosheets could be one-pot prepared with high quality
and quantity. In a typical experiment, 3.55 g of Zn(NO3)2·6H2O
were dissolved into 25mL of distilled water to obtain the zinc
nitrate solution (0.48 M), and 4.0 g of TEA were dissolved into 25mL
of distilled water to form the TEA solution (1.07 M). The above
solutions were mixed at 25 ◦C in a water bath equipped with a magnetic
stirrer. The colorless clear solution was obtained, with the pH
∼8.0. Then the temperature was rapidly increased to 80 ◦C with
continuous stirring for 3.0 h. The clear solution gradually became
colloidal during the increase of the temperature. The as-prepared
sample showed strong yellow-orange emission under UV irradiation
(365 nm) at room temperature, indicating the formation of
the ZnO nanostructures in the solution. The sample was then centrifuged
at 1500rpm for 10 min to discard the supernatant. The ZnO
colloidal precipitate was washed with absolute ethanol and water,
successively, and then air-dried in an oven at 40 ◦C. The maximum
final amount of the produced ZnO nanocrystals was about 0.9 g per
batch.