1. Department of Chemistry and the Waterloo Institute for Nanotechnology, University of Waterloo, Ontario N2L 3G1, Canada
2. Joint Center for Energy Storage Research, Argonne National Laboratory, Lemont, Illinois 60439, USA
3. Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
4. Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA
5. Department of Materials Science and Engineering, UC Berkeley, Berkeley, California 94720, USA