Synthesis and characteristics of complex multicomponent oxides prepared by polymer complex method

This account focuses on the synthesis and characteristics of ceramics prepared by the Pechini-type in-situ polymerizable complex (IPC) method. The current status of the LPC method is reviewed, and the principle and underlying chemistry of the IPC method is illustrated with a special emphasis on its intrinsic advantage over other solution-based technologies. The method has the ability to prepare complex multicomponent oxides with good homogeneity through mixing at the molecular level. The importance of "polymerization" itself in the IPC route is demonstrated by comparing with the non-polymerizable so-called amorphous citrate method, which affords less compositional homogeneity. The use of heterometallic complexes in the IPC processing is shown to be one of the most promising techniques to synthesize ceramics with exceptionally good homogeneity. It is one function of this account to describe how Raman and C-13 NMR spectroscopies can be effectively used for characterizing precursors in the IPC processing. Finally, it is demonstrated that another type of polymer complex solution (PCS) method overcomes the serious drawback of the IPC method; i.e. the amount of organics required for the PCS method is less than that required for the IPC method by a factor of about 20.