Untitled

Solid State Reactions in Cr<sub>2</sub>O<sub>3</sub>-ZnO Nanoparticles Synthesized by Triethanolamine Chemical Precipitation

“…In order to assess the influence of thermal treatment on the formation of Cr-ZnO (solid solution) and spinel ZnCr 2 O 4 nanoparticles, thermal analysis of the different as-prepared compositions was carried out. We can not expect the same thermal evolution as those reported in the literature by conventional processing [24], for the reason that in this case samples already started with solid solution, quasi-solid solution (2ZnO·Cr 2 O 3 ·H 2 O) or spinel composition at room temperature. Figure 7 presents the DTA curves plotted for each composition.…”

Reducibility and magnetic properties of nanosized ZnO substituted Fe2O3/TiO2system

“…[1][2][3][4][5][6][7][8][9][10][11][12] Several synthesis methods have been developed to obtain fine particles with controlled shapes and sizes 13,14 and particular magnetic properties. [14][15][16] Solid-solid interaction between Fe 2 O 3 and transition metal oxides to produce the corresponding ferrites is much influenced by the prehistory of parent oxide, their ratio and effect of additives. [17][18][19][20] These solid-solid interactions are controlled by thermal diffusion of reaction cation through the whole mass of each solid.…”

“…[17][18][19][20] These solid-solid interactions are controlled by thermal diffusion of reaction cation through the whole mass of each solid. [7][8][9][10][11][12][13][14][15][16] Soft ferrites in the CuZnTi system, having the formula Cu 12x Zn x Ti y Fe 22y O 4 , with 0?50(x(0?60 and 0?00( y(0?05 were investigated as a function of composition, sintering temperature and cooling speed, in order to obtain materials with controlled thermochromic (TC) and very high change rate of permeability with temperature around their TC. 21 The effect of Zn and Ti additions was a drastic change of the Curie temperature with about 10-12uC for each atomic percentage of Zn and Ti introduced into the spinel lattice while the cooling speed changed the behaviour of magnetic permeability with temperature around the Curie point.…”