Graphene oxide and simple molecules at high pressure: new perspectives for 2D nanoconfined chemistry of carbon based materials

Graphene oxide (GO) has recently emerged as a versatile platform material for the large-scalesynthesis of graphene and for the chemical functionalization of related 2D materials. In particularN-doping of these systems is a highly relevant topic for potential applications to energetic andenvironmental issues.1 From the structural point of view, the intriguing properties of GO are relatedto its layered structure featuring sufficiently large interlayer spacing for molecular insertion. 2Whereas a large variety of methods have been reported to explore the reactive behavior of GO atambient pressure, mainly at high temperature in gas phase or in solution, with the only exception ofa few structural studies, the high pressure chemistry of this material remains substantiallyunexplored.The idea of this study is to use pressure for inserting molecule between the GO layers and realizehigh density conditions, where bond breaking and reconstruction can occur, leading to theincorporation of heteroatoms or to the functionalization of the carbon framework by molecularfragments. For this purpose the room temperature high pressure behavior of pure GO and of GO inpresence of atomic and molecular systems of increasing reactive character, such as Ar, N2 and NH3,were studied using a membrane Diamond Anvil Cell (DAC) by means of X-ray diffraction, FTIRand Raman spectroscopy. Electronic photoexcitation was also employed to generate highly reactivespecies in high density conditions for activating chemical reactivity.The presented results indicate the substantial stability of the underlying layered structure of GO atthe investigated pressure and provide indication for the high pressure incorporation of nitrogenfunctionalities within the carbon framework, thus suggesting an innovative approach for thechemical functionalization of nanostructured graphene related systems and opening newperspectives for the synthesis of 2D advanced functional materials.4References[1] H. Wang, T. Maiyalagan, X. Wang ACS Catal. 2, 781 (2012).[2] D. R. Dreyer, A. D. Todd, C. W. Bielawski Chem. Soc. Rev. 43, 5288 (2014).[3] D. Talyzin, V. L. Solozhenko, O. O. Kurakevych, T. Szabó, I. Dékáni, A. Kurnosov, and V. DmitrievAngew. Chem. Int. Ed. 47, 8268 (2008).[4] M. Ceppatelli, D. Scelta, G. Tuci, G. Giambastiani, M. Hanfland, R. Bini, Carbon 93, 484 (2015).