Our group investigates the latest developments of electronic ceramics such as ceramic capacitors based on heterogeneous dielectrics; evolution of surface nanostructures in metal oxide systems; sensors based on p-n heterocontacts; semiconducting and metallic metal oxides; ferroelectric and piezoelectric materials; and other exploratory works in ceramic materials. Our major current research interests have been listed below.

Current Research Activities

Energy Capacitors

Many emerging technologies have electrical energy storage requirements that are not met by existing materials and devices. This includes devices over many scales, from those that power portable or micro-flight systems, to electric-powered vehicles, to electric weapon systems, to high power devices active on the electrical grid. This project is focused on the development of new dielectric materials packaged into portable capacitive devices capable of delivering a target electrical energy density of 100 Joules per cubic centimeter. This approach has the potential to break the trend in energy storage devices by increasing energy density without significant loss of power density.

Lead-free Piezoelectric Materials

Perovskite Pb(Zr,Ti)O3 (PZT) ceramics are widely used for many industrial applications, however there have been environmental concerns with PZT related to the toxicity of lead oxides which are volatile during processing. Consequently, this has motivated the search for lead free piezoelectric materials with piezoelectric properties comparable to PZT with a reduced environmental impact. We are investigating ceramic solid solutions within the perovskite system with an emphasis on fatigue properties for actuator applications, and on materials suitable for piezoelectric energy harvesting applications.

High Temperature Capacitors and Piezoelectric Materials

The development of a new family of high temperature piezoelectric materials is of significant technological interest for aerospace applications. There is great potential for piezoelectric materials to be used as actuators and sensors at elevated temperatures in order to enhance engine efficiency and as a component in engine health monitoring systems. All current piezoelectric materials have maximum operating temperatures below 200°C due to irreversible depolarization processes. This project is a collaborative effort between Oregon State University and the NASA Glenn Research Center focused on the development of a new family of ferroelectric piezoelectric materials for high temperature applications.