Abstract
Graphene-cellulose interactions have considerable potential in the development of new materials. In previous computational work (Biomacromolecules 2016, 16, 1771), we predicted that the model 100 hydrophobic surface of cellulose interacted favourably with pristine graphene in aqueous solution molecular dynamics simulations; conversely, a model of the hydrophilic 010 surface of cellulose exhibited progressive rearrangement to present a more hydrophobic face with the graphene, with weakened hydrogen bonds between cellulose chains and partial permeation of water. Here, we extend this work by simulating the interaction in aqueous solution of the amphiphilic 110 surface of a cellulose Iβ microfibril model, comprising 36 chains of 40 glucosyl residues, with an infinite sheet of pristine graphene. This face of the microfibril is of intermediate hydrophilicity and progressively associates with graphene over replicate simulations. As cellulose chains adhere to the graphene surface, forming CH-π and OH-π interactions, we observe a degree of local and global untwisting of the microfibril. Complementary rippling of the graphene surface is also observed, as it adapts to interaction with the microfibril. This adsorption process is accompanied by increased exclusion of water between cellulose and graphene although some water localises between chains at the immediate interface. The predicted propensity of a cellulose microfibril to adsorb spontaneously on the graphene surface, with mutual restructuring, highlights the amphiphilic nature of cellulose and the types of interactions that can be harnessed to design new graphene-carbohydrate biopolymer materials.
Original language | English |
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Article number | 108336 |
Journal | Journal of Molecular Graphics and Modelling |
Volume | 118 |
Early online date | 19 Sept 2022 |
DOIs | |
Publication status | Published - 2022 |
Bibliographical note
Funding Information:This work made use of computational support by CoSeC, the Computational Science Centre for Research Communities, which was made available through the Material Chemistry Consortium. S.J.E. is supported by an Engineering and Physical Sciences Research Council ( EPSRC ) fellowship on grant no. EP/V002651/1 .
Publisher Copyright:
© 2022 The Author(s)