NIRT: Novel Energy Conversion Devices Based on Nanowire Heterostructures

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

This proposal was received in response to NSE, NSF-0019. The goal of this proposal is to develop the scientific and engineering foundations of a broad range of energy conversion devices based on the novel approach of using 1-D semiconducting nanowire heterostructures. These heterostructures will consist of nanowires made of two or more single crystal semiconducting materials that are spatially arranged in such a manner that confinement effects are exploited in new and unique ways. The approach will rely on a promising chemical synthesis technique called vapor-liquid-solid (VLS) process that can be used to grow monocrystalline nanowires Si, Ge, SiGe, ZnO and various III-V and II-VI semiconductors. Electron and phonon confinement as well as the availability of new material phases in nanowire heterostructures will be used to tailor electronic, thermal, thermoelectric, optical and electromechanical properties. Based on the fundamental understanding of these properties, three different types of integrated devices will be developed to convert energy between thermal, mechanical, optical, and mechanical forms. The first will concentrate on high-performance thermoelectric devices for refrigeration and power generation. The second will investigate light emitting devices that can be used for low-loss coupling to optical fibers. Finally, the piezoelectric properties will be used for developing nanoelectromechanical sensors and actuators.