1. Institute of Condensed Matter and Nanosciences, Molecular Chemistry, Materials and Catalysis, Université catholique de Louvain, Louvain-la-Neuve B-1348, Belgium.
2. College of Materials Science and Engineering, Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology, Hunan University, Changsha 410082, Hunan, P. R. China.
3. Institutul Național de Cercetare-Dezvoltare pentru Tehnologii Izotopice și Moleculare Cluj-Napoca, Cluj-Napoca, România.