[1] Rice Univ, Dept Chem, 6100 Main St, Houston, TX 77005 USA
[2] Rice Univ, Smalley Curl Inst, 6100 Main St, Houston, TX 77005 USA
[3] Rice Univ, NanoCarbon Ctr, 6100 Main St, Houston, TX 77005 USA
[4] Rice Univ, Dept Mat Sci & NanoEngn, 6100 Main St, Houston, TX 77005 USA