The production and applications of ceramic oxide materials

In the ceramics field many of the new advanced ceramic oxides have a specially prepared mixture of cations which determines the crystal structure, through the relative sizes of the cations and oxygen ions, and the physical properties through the choice of cations and tlreh oxidation states. These include, for example, solid electrolytes and electrodes for sensors and fuel cells, fenites and garnets for magnetic systems, zirconates and titanates for piezoelectric materials, as well as ceramic superconductors and a number of other substances 

Chemical vapour deposition Example. The preparation of films of titanium dioxide. 

TiCU + Oafor 2H2O) — TiOa + 2CI2 (or 4HC1) 

Spray drying of aqueous suspensions Example. (Ni, Zn, Fe) sulphates (in air) — Ni, Zn ferrite. 

Example. (Ca, ZrO) nitrates - - (COOH)2 — (Ca, ZrO)(COO)2 calcium and zirconyl nitrates solution to which oxalic acid is added. The oxalate solid solution of cations is then fired to 1300 K 

Hydrolysis of metal-organic solutions Example. Ba(OC3H7)2 + Ti(OC5Hn)4 + H20 — BaTi03 Barium isopropoxide and Titanium tertiary amyloxide are refluxed in isopropanol and then hydrolyzed with de-ionized water to produce a sol-gel.  

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