Zinc hydroxyacetate and its transformation to nanocrystalline zinc oxide

The synthesis of nanocrystalline ZnO by thermal decomposition of zinc hydroxyacetate, Zn5(OH)8(CH3CO 2)2·nH2O, was investigated. The decomposition process was examined using X-ray diffraction, thermogravimetric analysis, mass spectrometry, electron microscopy, Brunauer-Emmett-Teller surface area analysis, and solid-state NMR spectroscopy. Intermediate Zn 5(OH)8(CH3CO2)2· nH2O phases form at temperatures up to 110 C from the starting compound Zn5(OH)8(CH3CO2) 2·2H2O by partial dehydration. At ∼110 C, 4 equiv of ZnO and 1 equiv of Zn(CH3CO2)2 are formed. Further heating causes Zn(CH3CO2)2 to decompose to acetone, acetic acid, acetic anhydride, and ZnO. Notably, a portion of Zn(CH3CO2)2 sublimes during the process. Overall, the product of the calcination is equiaxed ZnO nanocrystals of 20-100 nm diameter. © 2012 American Chemical Society