Abstract: Nano-sized zinc oxide（ZnO） powder was prepared by carbon adsorption hydrothermal method with crude zinc oxide and glacial acetic acid as raw materials.The calcination temperature，crystalline phase，particle size，and optical absorption properties of the as-prepared ZnO were characterized by means of thermogravimetric analysis-differential thermal analysis（TG-DTA），X-ray diffraction（XRD），transmission electron microscope（TEM），and UV-Vis spectroscopy etc..Results showed adsorption of activated carbon could prevent powder′s agglomeration during the preparation，drying，and calcination processes．Nano-sized ZnO with average grain size of 20 nm and surface area of about 85.25 m2/g was prepared at 600 ℃， which had uniform size，high dispersion behavior，and little agglomeration.The result of photocatalytic reaction for the degradation of methyl orange under ultraviolet light radiation showed the degradation of methyl orange almost complete（the degradation rate was 97%） in 60 min．

Key words: carbon adsorption, ZnO, photocatalysis, methyl orange