Self-supporting nanowire arrays templated in sacrificial branched porous anodic alumina for thermoelectric devices

Kalapi G. Biswas, Purdue University - Main Campus
Hatem El Matbouly, Purdue University - Main Campus
Vijay Rawat, Purdue University - Main Campus
Jeremy L. Schroeder, Birck Nanotechnology Center, Purdue University
Timothy D. Sands, Purdue University

Abstract

Templated synthesis of thermoelectric nanowires in porous anodic alumina (PAA) have potential for enhanced performance relative to bulk materials. A significant challenge is the template material, which can serve as a thermal shunt. In this work, an approach for creating a branched PAA template is described. The process utilizes localized self-heating to destabilize the planar anodization front, yielding branched and interconnected pores growing at a rate of 300 mu m/h. The template is selectively etched after electrodeposition of desired materials, yielding self-supporting nanowire arrays with thicknesses up to about 300 mu m, thereby eliminating the thermal shunt through the template.

Discipline(s)

Engineering | Nanoscience and Nanotechnology