1. A.J. Drexel Nanomaterials Institute, Drexel University, Philadelphia, PA 19104, USA.
2. Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104, USA.
3. Graphene Labs, Istituto Italiano di Tecnologia, 16163 Genova, Italy.
4. BeDimensional Spa, 16163 Genova, Italy.
5. Center for Advancing Electronics Dresden (CFAED), Technische Universität Dresden, 01062 Dresden, Germany.
6. Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, 01062 Dresden, Germany.
7. Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305, USA.