This research was funded by the European Commission Horizon 2020 Marie Sklodowska-Curie Individual Fellowships: NanoERA. Grant No.660960.

The financial support of the European Commission and the logistic and scientific support of the Ca’ Foscari University of Venice are gratefully acknowledged. The research has been carried out in collaboration with BASF SE, Material Physics, Ludwigshafen, Germany and Heriot-Watt University, Nanosafety Research Group, UK.