[1] Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA
[2] Univ Calif Santa Barbara, Dept Chem Engn, Santa Barbara, CA 93106 USA
[3] Univ Calif Santa Barbara, Dept Mat, Santa Barbara, CA 93106 USA
[4] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA
[5] Univ Calif Santa Barbara, Dept Chem & Biochem, Santa Barbara, CA 93106 USA