Three dimensional Graphene Gaetano Guerra Department of Chemistry and Biology and INSTM Research Unit, Università di Salerno, via Ponte don Melillo, 84084 Fisciano (SA), Italy, [email protected]
The first part of the seminar will describe preparation procedures and structural characterizations of graphite oxide, chemically reduced graphite oxide, exfoliated graphite oxide (often referred as graphene oxide, GO), which are the generally used precursors for bulk production of graphene materials. The main emphasis will be given to the crystalline order along different crystal directions.1 The seminar will continue with description of preparation and characterization of Graphite Oxide Intercalation Compounds (GOIC).2 When small ions, mainly inorganic, are intercalated, the observed crystalline structures generally exhibit a 3D long-range order, with relatively small distance between graphene sheets (< 0.6 nm), along the stacking direction. These 3D ordered GOIC generally also present order in the organization of the guest species in the interlayer space. For the intercalation of bulky ions, mainly organic, or of polar polymers, on the contrary, the crystalline order is generally limited to the distance between the graphite layers, which can largely increase (also up to 5 nm).2 By using suitable organic cations, the formation of new GOICs exhibiting a long-range order in the organization of the guest species in the interlayer space as well as a large distance between graphene sheets, can be achieved (Scheme 1).2 An analogous behaviour is observed for clay intercalates.3
Scheme 1. Progressive large increase of the interlayer spacing going from G, GO, GO/2HT to GO/2HT-SAES.
The catalytic activity of high-surface-area graphites and graphene oxide toward many organic reactions will be discussed.5 The final part of the lecture will be devoted to three dimensional (3D) graphene: flexible paper, aerogels and polymer composites based on graphene oxide and graphene. As for graphene paper, possible routes for preparation of flexible and solvent resistant films is discussed. As for aerogels, most of the presentation will be concentrated on polymeric aerogels with large amount of graphene, which can be used as masterbatches for polymer processing.5 As for polymer nanocomposites, the relevant influence of edge-carboxylation of graphite based materials on mechanical and electrical properties of polymer composites will be discussed.6 The technologically relevant catalytic activity of graphene nanofillers on the curing (crosslinking) reactions of thermoset resins will be also presented.7 References [1] Mauro, M.; Cipolletti, V.; Galimberti M.; Longo, P.; Guerra G. J. Phys. Chem. C. 2012, 116, 24809. [2] Mauro, M.; Maggio, M.; Cipolletti, V.; Galimberti, M.; Longo, P.; Guerra, G. Carbon 2013, 61, 395. [3] Cipolletti, V.; Galimberti, M.; Mauro, M.; Guerra, G. Appl. Clay Sci. 2014, 87, 179. [4] (a) Chu, X.; Zhu, Q.; Dai, W. L.; Fan, K. RSC Adv. 2012, 2, 7135. (b) Dreyer, D.R.; Bielawski, C.W. Adv. Funct. Mater. 2012, 12, 3247. (c) Acocella, M.R.; Mauro, M.; Falivene, L.; Cavallo, L.; Guerra, G. ACS Catalysis 2014, 4, 492. (d) Acocella, M.R.; Mauro, M.; Guerra, G. ChemSusChem 2014, 7, 3279. [5] (a) Longo, S.; Mauro, M.; Daniel, C.; Galimberti, M.; Guerra, G. Frontiers in Chemistry 2013, 1, Article 28; doi: 10.3389/fchem.2013.00028. (b) Longo, S.; Mauro, M.; Daniel, C.; Musto, P.; Guerra, G. Carbon 2014, 77, 896. [6] (a) Jeona, I.-Y.; Shina, Y.-R.; Sohna, G.-J.; Choia, H.-J.; Baea, S.-Y.; Mahmooda, J.; Junga, S.-M.; Seoa, J.-M.; Kima, M.-J.; Changa, D.W.; Daia, L.; Baeka, J.-B. PNAS 2012, 109, 5588. (b) Guadagno, L.; Raimondo, M.; Vertuccio, L.; Mauro, M.; Guerra, G.; Lafdi, K.; De Vivo, B.; Lamberti, P.; Spinelli, G.; Tucci, V., in preparation [7] Mauro, M.; Acocella,M.R.; Esposito Corcione, C.; Maffezzoli, A.; Guerra, G. Polymer 2014, 55, 5612.
The first part of the seminar will describe preparation procedures and structural characterizations of graphite oxide, chemically reduced graphite oxide, exfoliated graphite oxide (often referred as graphene oxide, GO), which are the generally used precursors for bulk production of graphene materials. The main emphasis will be given to the crystalline order along different crystal directions.1 The seminar will continue with description of preparation and characterization of Graphite Oxide Intercalation Compounds (GOIC).2 When small ions, mainly inorganic, are intercalated, the observed crystalline structures generally exhibit a 3D long-range order, with relatively small distance between graphene sheets (< 0.6 nm), along the stacking direction. These 3D ordered GOIC generally also present order in the organization of the guest species in the interlayer space. For the intercalation of bulky ions, mainly organic, or of polar polymers, on the contrary, the crystalline order is generally limited to the distance between the graphite layers, which can largely increase (also up to 5 nm).2 By using suitable organic cations, the formation of new GOICs exhibiting a long-range order in the organization of the guest species in the interlayer space as well as a large distance between graphene sheets, can be achieved (Scheme 1).2 An analogous behaviour is observed for clay intercalates.3
Scheme 1. Progressive large increase of the interlayer spacing going from G, GO, GO/2HT to GO/2HT-SAES.
The catalytic activity of high-surface-area graphites and graphene oxide toward many organic reactions will be discussed.5 The final part of the lecture will be devoted to three dimensional (3D) graphene: flexible paper, aerogels and polymer composites based on graphene oxide and graphene. As for graphene paper, possible routes for preparation of flexible and solvent resistant films is discussed. As for aerogels, most of the presentation will be concentrated on polymeric aerogels with large amount of graphene, which can be used as masterbatches for polymer processing.5 As for polymer nanocomposites, the relevant influence of edge-carboxylation of graphite based materials on mechanical and electrical properties of polymer composites will be discussed.6 The technologically relevant catalytic activity of graphene nanofillers on the curing (crosslinking) reactions of thermoset resins will be also presented.7 References [1] Mauro, M.; Cipolletti, V.; Galimberti M.; Longo, P.; Guerra G. J. Phys. Chem. C. 2012, 116, 24809. [2] Mauro, M.; Maggio, M.; Cipolletti, V.; Galimberti, M.; Longo, P.; Guerra, G. Carbon 2013, 61, 395. [3] Cipolletti, V.; Galimberti, M.; Mauro, M.; Guerra, G. Appl. Clay Sci. 2014, 87, 179. [4] (a) Chu, X.; Zhu, Q.; Dai, W. L.; Fan, K. RSC Adv. 2012, 2, 7135. (b) Dreyer, D.R.; Bielawski, C.W. Adv. Funct. Mater. 2012, 12, 3247. (c) Acocella, M.R.; Mauro, M.; Falivene, L.; Cavallo, L.; Guerra, G. ACS Catalysis 2014, 4, 492. (d) Acocella, M.R.; Mauro, M.; Guerra, G. ChemSusChem 2014, 7, 3279. [5] (a) Longo, S.; Mauro, M.; Daniel, C.; Galimberti, M.; Guerra, G. Frontiers in Chemistry 2013, 1, Article 28; doi: 10.3389/fchem.2013.00028. (b) Longo, S.; Mauro, M.; Daniel, C.; Musto, P.; Guerra, G. Carbon 2014, 77, 896. [6] (a) Jeona, I.-Y.; Shina, Y.-R.; Sohna, G.-J.; Choia, H.-J.; Baea, S.-Y.; Mahmooda, J.; Junga, S.-M.; Seoa, J.-M.; Kima, M.-J.; Changa, D.W.; Daia, L.; Baeka, J.-B. PNAS 2012, 109, 5588. (b) Guadagno, L.; Raimondo, M.; Vertuccio, L.; Mauro, M.; Guerra, G.; Lafdi, K.; De Vivo, B.; Lamberti, P.; Spinelli, G.; Tucci, V., in preparation [7] Mauro, M.; Acocella,M.R.; Esposito Corcione, C.; Maffezzoli, A.; Guerra, G. Polymer 2014, 55, 5612.
