1. Department of Physics,
Materials
Science and Engineering Program, Department of Electrical, Computer,
and Energy Engineering, and Liquid Crystals Materials Research Center, University of Colorado at Boulder, Boulder, Colorado
80309, United States
2. National Renewable Energy Laboratory, Golden, Colorado 80401, United States
3. Department of Chemistry, Rice University, Houston, Texas 77005, United States
4. Renewable and Sustainable Energy
Institute, National Renewable Energy Laboratory and University of Colorado at Boulder, Boulder, Colorado 80309, United
States