1. Istituto di Nanotecnologia CNR-Nanotec; Polo di Nanotecnologia c/o Campus Ecotekne; Via Monteroni 73100 Lecce Italy
2. King Abdullah University of Science and Technology (KAUST); Physical Sciences and Engineering Division (PSE), and KAUST Solar Center (KSC); Thuwal 23955-6900 Saudi Arabia
3. Dipartimento di Matematica e Fisica “E. De Giorgi,”; Università del Salento; Via per Arnesano 73100 Lecce Italy
4. Dipartimento di Ingegneria dell'Innovazione; Università del Salento; Via per Arnesano 73100 Lecce Italy
5. Department of Materials and Centre for Plastic Electronics; Imperial College London; Exhibition Road London SW7 2AZ UK
6. School of Materials Science and Engineering and School of Chemical and Biomolecular Engineering; Georgia Institute of Technology; 311 Ferst Drive Atlanta GA 30332 USA