Water Permeates and Plasticizes Amorphous Carbon Dots: Unraveling the Inner Accessibility of the Nanoparticles by Glass Transition Studies
Abstract
AbstractCarbon dots (CDs) are highly versatile nanomaterials with promising applications across catalysis, sensing, biotechnology, and optoelectronics. Yet, despite the widespread interest, their internal structure and permeability to solvents remain poorly understood. In this study, novel insights are provided into the plasticizing effect of water on amorphous CDs, addressing a critical gap in the current knowledge. A new class of polyamide‐based CDs is synthesized via a microwave‐assisted reaction using an amino acid and a small polyamine in water, systematically varying reaction times (3 – 60 min) to tailor the compactness of the carbon core. These findings reveal that water can permeate the internal structure of CDs and act as a plasticizer, significantly lowering their glass transition temperature, as shown by calorimetric analyses. Less compact CDs absorbed more water, while denser ones showed lower permeability. These trends are further corroborated by X‐ray scattering data. This report clearly demonstrates that the carbonaceous core of CDs is accessible to water, challenging the assumption that the nanoparticles are structurally impermeable. These results lay the groundwork for new structural models of CDs and open exciting opportunities for diffusion studies, functional design, and targeted applications in nanoscience.
Article Details
Authors (9)
Elisa Sturabotti
Center for Cooperative Research in Biomaterials (CIC biomaGUNE) Basque Research and Technology Alliance (BRTA) Donostia – San Sebastián 20014 Spain
Valerio Di Lisio
Centro de Física de Materiales (CSIC, UPV/EHU)-Material Physics Center (MPC) 1 , Paseo Manuel de Lardizabal 5, San Sebastian 20018,
Lucia Cardo
Center for Cooperative Research in Biomaterials (CIC biomaGUNE) Basque Research and Technology Alliance (BRTA) Donostia – San Sebastián 20014 Spain
Alessandro Camilli
Center for Cooperative Research in Biomaterials (CIC biomaGUNE) Basque Research and Technology Alliance (BRTA) Donostia – San Sebastián 20014 Spain
Estela Moretón Alfonsín
Center for Cooperative Research in Biomaterials (CIC biomaGUNE) Basque Research and Technology Alliance (BRTA) Donostia – San Sebastián 20014 Spain
Daniele Cangialosi
Centro de Física de Materiales (CSIC, UPV/EHU)-Material Physics Center (MPC) 1 , Paseo Manuel de Lardizabal 5, San Sebastian 20018,
Amaia Iturrospe Ibarra
Centro de Fisica de Materiales (CFM‐MPC) CSIC‐UPV/EHU Paseo Manuel de Lardizabal 5 Donostia ‐ San Sebastián E‐20018 Spain
Arantxa Arbe
Centro de Física de Materiales (CSIC, EHU) and Materials Physics Center MPC , Paseo Manuel de Lardizabal 5, E-20018 San Sebastián,
Maurizio Prato
Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via Licio Giorgieri 1, Trieste 34127, Italy