Progress Toward Wafer-Scale Thermionic Energy Converters

Thermionic energy converters (TECs) are simple heat engines that were conceived in 1915, demonstrated in 1939, and were the focus of major research programs from 1960 through 2000 for space nuclear power. TEC research has recently seen the beginning of a revival based on new fabrication technology, materials, and device designs. The use of micro electromechanical systems (MEMS) processes for TEC fabrication is an attractive route to overcoming some of the design challenges and to dramatically reducing manufacturing costs.

Over the past decade, researchers at Stanford have investigated wafer-scale processes for thermally isolated cathode structures, low work function anodes, and thermal isolation structures, as well as a new concept, the photon-enhanced thermionic energy converter. My talk will provide an overview of recent progress in this technology around the world, its applications, and my perspectives on the remaining challenges for this potentially important energy conversion technology.