[1] Univ Trieste, Dept Chem & Pharmaceut Sci, ICCOM CNR, Consortium INSTM, I-34127 Trieste, Italy
[2] Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA
[3] Univ Penn, Dept Chem, Philadelphia, PA 19104 USA
[4] Brookhaven Natl Lab, Ctr Funct Nanomat, Upton, NY 11973 USA
[5] Univ Penn, Dept Chem & Biomol Engn, Philadelphia, PA 19104 USA