Controlling Morphologies and Tuning the Related Properties of Nano/Microstructured ZnO Crystallites

In this paper, we successfully synthesized three kinds of typical ZnO micro/nanocrystallites including flakes, columns, and pyramids by means of different facile wet chemical routes. The growth environment plays a crucial role in the morphologies of these ZnO micro/nanocrystallites. At the same time, we find that physical/chemical properties of these ZnO samples are dependent on their exposed surface, and the order of gas sensing and photocatalytic efficiency of the ZnO crystal planes is (0001) > {10 (1) over bar0} > {10 (1) over bar1} and (000 (1) over bar). On the basis of structural analyses of various exposed surfaces and related X-ray photoelectron spectroscopy, we deeply discussed the effect of definite surface structures on their gas sensing and photocatalytic properties.