Sorption of polar organic solvents and water by graphite oxide: Thermodynamic approach

Korobov, M.V.; Talyzin, Alexandr V.; Ребрикова, А.Т.; Shilayeva, Elizaveta A.; Авраменко, Н. В.; Gagarin, Alexander N.; Ferapontov, N. B.

doi:10.1016/j.carbon.2016.02.070

Cited by 47 publications

(101 citation statements)

References 38 publications

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“…acetone, acetonitrile, DMF). [29,44] Surprisingly, the difference between structure and swelling properties of BGO1 and BGO2 is rather small. For example, the d(001)= 8.93Å and d(001)=9.05Å are found for powder immersed in excess of liquid methanol for BGO1 and BGO2 oxidations, respectively.…”

Section: Structure and Swelling Of Brodie Vs Hummers Gomentioning

confidence: 99%

Brodie vs Hummers graphite oxides for preparation of multi-layered materials

Talyzin

Mercier

Klechikov

et al. 2017

Carbon

110

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Graphite oxides synthesized by one and two step Brodie oxidation (BGO) andHummers (HGO) methods were analysed by a variety of characterization methods in order to evaluate the reasons behind the difference in their properties. It is found that the Brodie method results in a higher relative amount of hydroxyl groups and a more homogeneous overall distribution of functional groups over the planar surface of the graphene oxide flakes. The higher number of carbonyl and carboxyl groups in HGO, detected by several methods, including XPS, NMR and FTIR, unavoidably results in defects of the graphene "skeleton", holes and overall disruption of the carbon-carbon bond network, stronger deviation from planar flake shape and poor ordering of the graphene oxide layers. It is also suggested that functional groups in HGO are less homogeneously distributed over the flake surface, forming some nanometer-sized graphene areas. The presence of differently oxidized areas on the GO surface results in inhomogeneous solvation and hydration of HGO and effects of inter-and intrastratification. The proposed interpretation of the data explains the higher mechanical strength of multi-layered BGO membranes/papers, which are also less affected by humidity changes, thus providing an example of a membrane property superior to that of HGO.

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Section: Structure and Swelling Of Brodie Vs Hummers Gomentioning

confidence: 99%

Brodie vs Hummers graphite oxides for preparation of multi-layered materials

Talyzin

Mercier

Klechikov

et al. 2017

Carbon

110

View full text Add to dashboard Cite

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“…This led to improved selectivity of GO membranes for gas phase separations [3,33]. Thermodynamic simulations performed by Korobov et al suggest the different extent of intercalation of various solvent molecules in GO nanochannels [34]. Due to these differences in interactions, it may not be possible to predict the performance of GO membranes with organic solvents from their performance with aqueous solutions.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of graphene oxide membranes and their behavior in water and isopropanol

Aher

Cai

Majumder

et al. 2017

Carbon

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Graphene oxide (GO) membrane has been synthesized on commercial polysulfone ultrafiltration membranes (Pore size: 17 nm) using the drop casting method followed by baking at 90 C for 24 h. Baking resulted in the reduction of GO and removal of bulk water intercalated in the GO sheets. Deposited GO film showed high stability under shear stress variation. This work shows that water adsorption on the GO membrane determines its permeation performance. Despite the higher viscosity of isopropyl alcohol (IPA), its permeability was 7 times higher than water through the baked (“dry”) GO membranes, which were never contacted with water. However, IPA permeability of GO membranes dropped to 44% (of deionized water) when contacted with water (“hydrated” or “wet” GO membranes). Extensive size exclusion (rejection) studies with various dye and dendrimer molecules showed pore size reduced from 3.3 nm in the “dry” state to 1.3 nm in the “wet” state of GO membranes. FT-IR characterization of GO membrane suggested adsorption of water on the nanochannels of the active layer. Also, significant decay in flux was observed for water (82% of its initial flux) as compared to IPA (38% of its initial flux) for initially dry GO membranes.

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“…Detailed characterization of these materials using XRD, FTIR, TGA and some other methods were presented in our previous publications. [30,40,44,48,56] The ref [56] provides characterization of the same materials as those which are used here for study of sugar alcohol intercalation. XRD data were recorded using in house diffractometers Siemens D5000…”

Section: Methodsmentioning

confidence: 99%

“…[45] Transitions between the phases with different number of intercalated solvent layers were found under variation of temperature or pressure. [40,42,45] Moreover, selective intercalation of methanol from water/methanol mixtures was observed for BGO. [46][47] In contrast, HGO shows no selectivity in sorption from binary mixtures, no phase transitions and absence of clearly distinct phases with certain amount of intercalated solvent.…”

Section: Introductionmentioning

confidence: 91%