Abstract: Various morphologies and different sized ZnO nanorods and microrods are synthesized onto glass substrates through a low-temperature,environmental benign,solution-based growth method by the source of zinc acetate and catalysts of hexamethylene tetramine or triethanolamine.The influence of the pH values and the concentration on the morphology of as-grown ZnO rods is discussed and the growth habits is analyzed.With increasing the concentration,the ratio of length to diameter gets small and the distribution of ZnO rods on the glass substrate changes from out of order to distribution along the growth axis c.When the pH value is from weak acid to weak alkali,the shape of ZnO samples gets from the long column to short one-pair rods grown symmetrically from one center to both sides.With the pH values further increasing,it can be grain.Regular hexagonal ZnO rods arrays can be fabricated by the control of certain pH and concentration of the solution.XRD,SEM, and PL are used to analyze the structure,morphology, and optical properties.The PL spectrum of the regular hexagonal ZnO rods shows that there is a broad green band with a peak at 530nm and a FWHM of 220nm.The green emission is attributed to the recombination of an electron in Vo+ to a hole in VB.

Key words: ZnO, nanorods, photoluminescence, chemical solution method, crystal growth