A promising n-type thermoelectric oxide, based on the tungsten bronze-structured ferroelectric Sr x Ba 1-x Nb 2 O 6-d (SBN, x~0.61), was investigated to enhance the thermoelectric power factor through templated grain growth (textured polycrystalline). In the reduced SBN textured, both the electrical conductivity (r) and the magnitude of thermopower (S) are increased in the c axis: r 33 . r 11 and |S 33 | . |S 11 |, and consequently, the thermoelectric power factor (PF) increased significantly due to crystal anisotropy and grain boundary density reduction. It was found in randomly oriented polycrystalline ceramics that the thermoelectric properties are dominated by a-axis properties. A ferroelectric-thermoelectric anomaly is observed at 4mm-4/mmm phase transition temperature (T C ) and depends on temperature and reduction degree, consistent with our earlier observations in single crystal SBN. Above T C , the carrier transport mechanism is controlled by polaron hopping conduction, and below T C the behavior depends on the degree of reduction. However, the magnitude of the Seebeck coefficient is dependent on the crystal anisotropy.

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Metallization with high conductivities is critical in the design of high performance multilayer electroceramic devices. Cold sintering offers exciting new opportunities in the integration of different material classes; here we explore novel metal chemistries and demonstrate their integration into ceramic multilayers. The processing is enabled due to the cosintering of both the ceramic and metal powders in fast times and at extremely low sintering temperatures. Metal powders are printed as pastes and formed into multilayers that can be cosintered with the ceramic ZnO; these specific metals include Cu, Fe, and Al. The multilayer structures are assembled and fabricated under a thick film process and enabled by using a polypropylene carbonate binder system that can be removed at low temperatures under N 2 −H 2 forming gas, permitting control of oxidation of the Cu, Fe, and Al. As a result, extremely high conductivity electrodes are fabricated and quantified through the equivalent series resistance (ESR). In addition, new electrode composite concepts, such as mixed particles of Fe−Cu cosintered in between the ZnO layers, are possible with the cold sintering process.