Carbon Nano-onions (Multilayer Fullerenes): Potassium Intercalation and Reductive Covalent Functionalization - Perez-Ojeda, M. Eugenia; Castro, Edison; Kröckel, Claudia; Lucherelli, Matteo Andrea; Ludacka, Ursula; Kotakoski, Jani; Werbach, Katharina; Peterlik, Herwig; Melle-Franco, Manuel; Chacon-Torres, Julio C.; Echgoyen, Luis; Hirsch, Andreas; et al. (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2022)