relation: https://khub.utp.edu.my/scholars/12863/ title: The True Amphipathic Nature of Graphene Flakes: A Versatile 2D Stabilizer creator: Kuziel, A.W. creator: Milowska, K.Z. creator: Chau, P.-L. creator: Boncel, S. creator: Koziol, K.K. creator: Yahya, N. creator: Payne, M.C. description: The fundamental colloidal properties of pristine graphene flakes remain incompletely understood, with conflicting reports about their chemical character, hindering potential applications that could exploit the extraordinary electronic, thermal, and mechanical properties of graphene. Here, the true amphipathic nature of pristine graphene flakes is demonstrated through wet-chemistry testing, optical microscopy, electron microscopy, and density functional theory, molecular dynamics, and Monte Carlo calculations, and it is shown how this fact paves the way for the formation of ultrastable water/oil emulsions. In contrast to commonly used graphene oxide flakes, pristine graphene flakes possess well-defined hydrophobic and hydrophilic regions: the basal plane and edges, respectively, the interplay of which allows small flakes to be utilized as stabilizers with an amphipathic strength that depends on the edge-to-surface ratio. The interactions between flakes can be also controlled by varying the oil-to-water ratio. In addition, it is predicted that graphene flakes can be efficiently used as a new-generation stabilizer that is active under high pressure, high temperature, and in saline solutions, greatly enhancing the efficiency and functionality of applications based on this material. © 2020 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim publisher: Wiley-VCH Verlag date: 2020 type: Article type: PeerReviewed identifier: Kuziel, A.W. and Milowska, K.Z. and Chau, P.-L. and Boncel, S. and Koziol, K.K. and Yahya, N. and Payne, M.C. (2020) The True Amphipathic Nature of Graphene Flakes: A Versatile 2D Stabilizer. Advanced Materials, 32 (34). ISSN 09359648 relation: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85087941106&doi=10.1002%2fadma.202000608&partnerID=40&md5=2ef12fd70c72b1779208868b39695f8d relation: 10.1002/adma.202000608 identifier: 10.1002/adma.202000608