1. Center of Excellence for Green Nanotechnologies Joint Centers of Excellence Program King Abdulaziz City for Science and Technology Riyadh 11442 Saudi Arabia
2. Department of Mechanical and Aerospace Engineering University of California, Los Angeles Los Angeles CA 90095 USA
3. National Center for Nanotechnology Materials Science Institute King Abdulaziz City for Science and Technology Riyadh 11442 Saudi Arabia
4. Department of Electrical and Computer Engineering University of California Los Angeles Los Angeles CA 90095 USA