Development of Tailored Graphene Nanoparticles: Preparation, Sorting and Structure Assessment by Complementary Techniques

settings Order Article Reprints This is an early access version, the complete PDF, HTML, and XML versions will be available soon. Open AccessArticle Development of Tailored Graphene Nanoparticles: Preparation, Sorting and Structure Assessment by Complementary Techniques by Kaiyue Hu 1 [ORCID] , Luigi Brambilla 1 [ORCID] , Patrizia Sartori 2 [ORCID] , Claudia Moscheni 3 [ORCID] , Cristiana Perrotta 3 [ORCID] , Lucia Zema 4,* [ORCID] , Chiara Bertarelli 1,5 and Chiara Castiglioni 1 [ORCID] 1 Dipartimento di Chimica, Materiali e Ingegneria Chimica Giulio Natta, Politecnico di Milano, 20133 Milano, Italy 2 Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, 20133 Milano, Italy 3 Dipartimento di Scienze Biomediche e Cliniche, Università degli Studi di Milano, 20157 Milano, Italy 4 Sezione di Tecnologia e Legislazione Farmaceutiche “M. E. Sangalli”, Dipartimento di Scienze Farmaceutiche, Università degli Studi di Milano, 20133 Milano, Italy 5 Center for Nano Science and Technology@PoliMi, Istituto Italiano di Tecnologia, 20133 Milano, Italy * Author to whom correspondence should be addressed. Molecules 2023, 28(2), 565; https://doi.org/10.3390/molecules28020565 Received: 9 November 2022 / Revised: 24 December 2022 / Accepted: 31 December 2022 / Published: 5 January 2023 (This article belongs to the Special Issue Materials Chemistry in Italy) Download Versions Notes Abstract We present a thorough structural characterization of Graphene Nano Particles (GNPs) prepared by means of physical procedures, i.e., ball milling and ultra-sonication of high-purity synthetic graphite. UV-vis absorption/extinction spectroscopy, Dynamic Light Scattering, Transmission Electron Microscopy, IR and Raman spectroscopies were performed. Particles with small size were obtained, with an average lateral size = 70–120 nm, formed by few = 1–10 stacked layers, and with a small number of carboxylic groups on the edges. GNPs relatively more functionalized were separated by centrifugation, which formed stable water dispersions without the need for any surfactant. A critical reading and unified interpretation of a wide set of spectroscopic data was provided, which demonstrated the potential of Specular Reflectance Infrared Spectroscopy for the diagnosis and quantification of chemical functionalization of GNPs. Raman parameters commonly adopted for the characterization of graphitic materials do not always follow a monotonic trend, e.g., with the particle size and shape, thus unveiling some limitations of the available spectroscopic metrics. This issue was overcome thanks to a comparative spectra analysis, including spectra deconvolution by means of curve fitting procedures, experiments on reference materials and the exploitation of complementary characterization techniques