Sintered materials surface morphologies

Modification of Vibrational Spectra of Diatomic Molecules Induced by the Adsorption on Oxide and Halide surfaces A method for Probing the Structures of the Adsorption Sites and the Surface Morphologies of Sintered Materials... 

The topics of surfaces and sintering will be new to most students. The short chapter on bonding and the chapters on amorphous materials and liquid crystals introduce new concepts. These are followed by treatment of molecular morphology. The final chapters are on magnetic materials, porous and novel materials, and the shape memory. 

NiO is a cubic oxide characterized by ionicity and lattice parameters very similar to those of MgO. Furthermore, the preparation procedures of the two oxides may be similar (i) Stoichiometric high-surface-area NiO is prepared (as is MgO) from the hydroxide precursor by decomposition under vacuum and (ii) low-surface-area materials are obtained by progressive sintering at high temperatures. The evolution of the microcrystal morphology on passing from high- to low-surface-area (sintered) NiO is also similar to that for MgO, as demonstrated by Escalona Platero et al. (73,265,266) the final habit of the microcrystals is represented by nearly perfect cubes predominantly defined by atomically flat (001) faces and terraces. 

Because the performance of spinel windows is also very sensitive to the quality of the precursor materials (both purity and morphology), there have been researches that can be found in the open literature. To produce better spinel precursor powders, various methods have been developed. For example, a new method has been used to synthesize spinel powders from boehmite, in which Mg " ion was metal exchanged onto the surface of boehmite particles [208]. In this method, particle size, size distribution, purity, and stoichiometry of the Mg-doped boehmite powders could be well controlled. Such powders exhibited good sinterability and resulted in spinel ceramics with desired optical properties. 

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