The research objective of this work is to understand how the mechanical behavior and structural stability of nanoporous silicon are influenced by the combined effects of small deformation volume and large surface-area-to-volume ratio. Silicon, with broad technological importance and wide current application, will serve as a model material for nanostructured non-metallic systems. Recently, a number of research groups have reported that nanoscale silicon structures exhibit ductile deformation below a critical size. Motivated by these results, this project will investigate the mechanical behavior of nanoporous silicon whose ligament structure consists of an interconnected network of fine silicon nanowires. The research approach combines computational and experimental methodologies and leverages an ongoing collaboration between the University of Kentucky and the Karlsruhe Institute of Technology. The proposed research specifically aims to structurally and mechanically characterize nanoporous silicon, and to simulate and model nanoporous silicon deformation. The investigators will utilize a battery of thin film and small-scale test techniques that have been established in Lexington (Kentucky) and Karlsruhe (Germany) as well as atomistic computational models to realize these aims. Combined results will then be leveraged to elucidate the structural stability, mechanical properties and deformation mechanisms of nanoporous silicon, particularly with respect to the role of dimensional constraints placed on silicon deformation by the nanoscale ligament structure.

Success in this research project will benefit efforts to more broadly incorporate nanostructured non-metals in technological applications, as well as the deployment of nanostructured silicon in industrially relevant engineering solutions. The proposed research establishes the fundamental understanding required by related device-level engineering efforts to develop next-generation photovoltaics, optical sensors, battery anodes, flexible electronics or nanoscale light-emitting diodes. In addition, the Kentucky-Karlsruhe collaboration will provide American students with hands-on laboratory experience in a world-class international research environment, German students with an opportunity to live and perform research in the USA, and all students the horizon-broadening opportunity to work with foreign peers in a science-focused cultural exchange.

Project Start
Project End
Budget Start
2013-07-01
Budget End
2017-06-30
Support Year
Fiscal Year
2013
Total Cost
$399,618
Indirect Cost
Name
University of Kentucky
Department
Type
DUNS #
City
Lexington
State
KY
Country
United States
Zip Code
40526