Grant: Research Tools and Instruments

Funds are requested for a rapid induction hot press (RIHP). It will provide critical new capabilities for metastable materials or those sensitive to ambient atmosphere, that are not available with Waterloo's current, conventional hot-press. This instrument (in Kleinke's lab) was installed 12 years ago to densify previous-generation thermoelectric (TE) metalloid-type materials. It is constantly breaking down due to age and is limited to air-stable materials. It is completely unusable for the research in the Nazar lab, and not suited to the new research directions in the Kleinke lab. Innovation in materials chemistry research is focused on designing specific material properties and understanding their relationship to amorphous or crystalline structure. A large portion of Nazar's program in solid state electrochemistry recently targets novel materials with solely ionic transport as solid-state electrolytes for Li and Na metal batteries. A range of new Li/Na superionic conductors under development are based on (thio)phosphates, sulfo-halides, oxides, and inorganic/polymer composite materials. Kleinke's NSERC-funded research centers on TE materials of fundamental and practical interest for more sustainable energy usage. Developing new advanced materials in these classes depends on physical property measurements of ion/ electrical/thermal conductivity and thermopower. They need to be conducted on highly dense pressed pellets to reflect the intrinsic properties.  RIHP is ideal for such purposes. Additionally, fabricating very thin ion-conductive inorganic membranes ( 97% density) for solid state batteries via RIHP is essential to a) minimize mass and volume in the cell; b) suppress grain boundaries that create hazardous metal dendrite growth. Almost all the solid electrolytes are moisture or CO2-sensitive and cannot be densified in the existing hot-press. Even with herculean efforts to load crystalline powders with minimal air-exposure, the fragility of these ceramics results in fracture upon attempted removal from the press. Material processing is also too slow for rapid consolidation needed to inhibit growth of unwanted phases. This renders poor quality samples and poorly functional solid electrolyte membranes. The proposed RHIP is an innovative type of system that operates using rapid inductive - instead of slow thermal - heating. Both the Nazar and Kleinke research teams now urgently require this vital tool, particularly for new materials that need to be processed under inert atmosphere, and at rapid heating rates. RIHP enables localized heating, and thus minimization of the grain boundaries and the impurities within those boundaries. There are no other cost-effective ways of preparing high-density solid-state electrolyte or thermoelectric samples other than RIHP. It is a unique tool that will provide vastly expanded processing abilities and rapid throughput.