1. Global Fuel Cell Business, General Motors Company, Pontiac, Michigan 48340, United States
2. Pajarito Powder, 3600 Osuna Road NE, Suite 309, Albuquerque, New Mexico 87109, United States
3. School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
4. Kavli Institute at Cornell for Nanoscale Science, Ithaca, New York 14853, United States