1. Department of Chemistry; Northwestern University; 2145 Sheridan Road Evanston IL 60208 USA
2. Institute of Functional Nano & Soft Materials (FUNSOM); Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices; Soochow University; 199 Ren'ai Road Suzhou 215123 China
3. Department of Materials Science and Engineering and the Materials Research Center; Northwestern University; 2220 Campus Drive Evanston IL 60208 USA
4. Applied Physics Program and the Materials Research Center; Northwestern University; 2220 Campus Drive Evanston IL 60208 USA
5. Polyera Corporation; 8045 Lamon Avenue Skokie IL 60077 USA