Porous, Functionally Gradient Pyroelectric Materials

• Published in: Journal of the American Ceramic Society Vol. 90; no. 1; pp. 137 - 142
• Main Authors: Shaw, Christopher P., Whatmore, Roger W., Alcock, Jeffrey R.
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01-01-2007; Blackwell; Wiley Subscription Services, Inc
• Subjects: Applied sciences; Boundary layer; Building materials. Ceramics. Glasses; Ceramic industries; Ceramic matrix composites; Chemical industry and chemicals; Electrotechnical and electronic ceramics; Exact sciences and technology; Experiments; Heat conductivity; Porosity; Technical ceramics; Scanning electron microscopy; Electrical properties; Functionnally graded material; Manufacturing; Pyroelectric material; Experimental study; Fabrication property relation; Porous material; Oxide ceramics; Electroceramics
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1551-2916.2006.01373.x

Properties of a new type of pyroelectric ceramic structure containing a layer of known porosity laminated between two dense layers, to form a functionally gradient material (FGM), are reported. The combination of theoretical models for pyroelectric, dielectric, and thermal properties gave a model for the pyroelectric voltage figure of merit (FV) in good agreement with experiment, which had shown a 20% improvement for an introduced central layer porosity of 27%. Preliminary pyroelectric responsivity measurements on FGM infrared detectors indicated an even better improvement. It is postulated that this is due to the porous layer acting as a thermal barrier in the structure.