کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1332748 | 979052 | 2008 | 6 صفحه PDF | دانلود رایگان |
The solid state interaction of the Zn1−xCoxO nominal system is investigated by means of diffusion couples and analysis of co-precipitated samples. The formation of a homogeneous Co:ZnO solid solution is found to be determined by the crystal structure from which CoII ions diffuse into the wurtzite lattice. No diffusion is observed whenever the CoO rock-salt structure is formed from the CoII precursor. On the contrary, the diffusion from the Co3O4 spinel phase is feasible but has a limited temperature range defined by the reduction at a high temperature of CoIII–CoII, since this process again leads to the formation of the rock-salt structure. However, when using a highly reactive and homogeneous co-precipitated starting powder, neither the spinel phase nor the rock-salt structure is formed, and a CoII:ZnO solid solution is obtained, which remains stable up to high temperatures.
Maximum diffusion distance for the ZnO–CoOx couple as a function of temperature. Dashed gray lines represent the temperature values at which the transformations between CoO and Co3O4 compounds take place.Figure optionsDownload as PowerPoint slide
Journal: Journal of Solid State Chemistry - Volume 181, Issue 9, September 2008, Pages 2456–2461