1. Materials Science and Engineering Program University of California San Diego La Jolla CA 92093‐0418 USA
2. Nano Engineering Department University of California San Diego La Jolla CA 92093‐0418 USA
3. Department of Photovoltaics and Materials Technology Sandia National Laboratories Albuquerque NM 87123 USA
4. Department of Geochemistry Sandia National Laboratories Albuquerque NM 87123 USA
5. Nanoscale Sciences Department Sandia National Laboratories Albuquerque NM 87123 USA