Operando study of water vapor transport through ultra-thin graphene oxide membranes

Eliseev, Andrei A.; Poyarkov, A.A.; Chernova, É. A.; Chumakov, Andrei; Konovalov, Oleg; Петухов, Д. И.

doi:10.1088/2053-1583/ab15ec

Cited by 27 publications

(24 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[5] In many studies, the driving force of vapor permeation is assumed to be a gradient of water pressure on opposite sides of membranes. [77,78] This pressure gradient (mbar) is significantly smaller compared to the pressure gradient (1-20 bar) used in pressure-driven filtration experiments. Since the permeance of membranes is usually expressed in units which include pressure, the small gradient of pressure due to difference in humidity between feed and permeate streams in pervaporation experiments results in calculations of huge values, e.g., ≈80 000 L/(m 2 bar h) even for quite common water flux.…”

Section: Discussionmentioning

confidence: 99%

Swelling Pressures of Graphite Oxide and Graphene Oxide Membranes in Water and Ethanol

Iakunkov

Boulanger

Nordenström

et al. 2021

Adv Materials Inter

View full text Add to dashboard Cite

the methods commonly used for the preparation of GO thin films and freestanding foils/membranes.Most of the applications cited above are enabled by the ability of GO multilayers to swell in polar solvents similarly to their precursor graphite oxides. [18][19][20][21][22] In this respect GO is similar to very common clay minerals, e.g., montmorillonites, [23] vermiculites, [24] and bentonites. [25] Swelling occurs in these materials due to sorption of water (or other solvents) between 2D layers and the expansion of interlayered distance. [26][27][28] The driving force of swelling is hydration of anions in clay minerals and hydration of interlayer functional groups in GO. The crystalline swelling refers to layer-by-layer intercalation of solvent. Osmotic swelling is controlled by the relatively easy flow of solvent in and out of structure regulated by osmotic effects. [29][30][31][32][33] Remarkably, crystalline swelling is found for Brodie GO in all so far studied solvents except water [34][35][36][37][38] while for Hummers GO only osmotic-like swelling was so far reported. [37,39,40] Adding water to clays under conditions of confinement is known to produce pressures in the range of tens or even hundreds of bar. [25,41,42] Swelling pressure is complex phenomena, which depends on many parameters, e.g., degree of compaction, [25] concentration of salts in solution, [43] temperature [44] etc. It is an important factor, e.g., in construction works since the pressure is sufficient to induce damage in buildings or roads. Swelling pressure has been studied in detail for clay minerals but so far not reported for multilayered GO and graphite oxides. At the same time, the swelling pressure is an important factor affecting performance of GO membranes.The swelling of GO membranes is directly related to the size of "permeation channels" which enable a flow of solvents and solutions. Strong variation in the size of the "permeation channels" is observed in GO membranes depending on the solvent used, [45] concentration and chemical nature of dissolved molecules or ions, [17] shelf storage time, [40] and many other parameters related to the preparation of membranes. For example, the swelling in liquid ethanol was reported with significant scatter providing d(001) values in the range ≈11-17.7 Å. [10,16,46,47] Swelling in longer alcohols provides interlayer distances up to ≈50 Å. [10,48] There are also examples showing that the swelling of GO membranes can be significantly different compared to precursor graphite oxides. [16,17] Strong variation of interlayer distance in swollen GO membranes is a problem for nanofiltration applications, which require Swelling of graphene oxide (GO) membranes and bulk graphite oxide under confinement conditions is found to produce pressures up to ≈220 bar. Swelling pressure is important to take into account in many applications of GO membranes, but it has not been previously reported. Swelling pressures are typically measured only for bulk materials. However, it is demonstrated that even µm thick GO ...

show abstract

Section: Discussionmentioning

confidence: 99%

Swelling Pressures of Graphite Oxide and Graphene Oxide Membranes in Water and Ethanol

Iakunkov

Boulanger

Nordenström

et al. 2021

Adv Materials Inter

View full text Add to dashboard Cite

show abstract

“…These results should allow precise control of the density of sheets deposited by the LB or Langmuir-Schaefer (LS) procedures. Graphene oxide is also extremely attractive for air and natural gas dehumidification and an operando study of ultrathin (50 nm) membranes by GID during air dehumidification has been reported [193]. It was found that the absorption of water vapor in graphene oxide layers follows a modified Kelvin equation similar to condensation in an elastic slit, whereas desorption of water is limited by a few outer layers.…”

Section: Liquid Interfacesmentioning

confidence: 99%

Synchrotron Scattering Methods for Nanomaterials and Soft Matter Research

Narayanan

Konovalov

2020

Materials

Self Cite

View full text Add to dashboard Cite

This article aims to provide an overview of broad range of applications of synchrotron scattering methods in the investigation of nanoscale materials. These scattering techniques allow the elucidation of the structure and dynamics of nanomaterials from sub-nm to micron size scales and down to sub-millisecond time ranges both in bulk and at interfaces. A major advantage of scattering methods is that they provide the ensemble averaged information under in situ and operando conditions. As a result, they are complementary to various imaging techniques which reveal more local information. Scattering methods are particularly suitable for probing buried structures that are difficult to image. Although, many qualitative features can be directly extracted from scattering data, derivation of detailed structural and dynamical information requires quantitative modeling. The fourth-generation synchrotron sources open new possibilities for investigating these complex systems by exploiting the enhanced brightness and coherence properties of X-rays.

show abstract

“…(4) The linear adsorption isotherm (or non-adsorption) for all gases on the surface of MXene lamellar membranes is neglected. (5) The mass transfer resistance of gas within the porous AAO layer is neglected due to its much large pore size [10,26].…”

Section: Theoretical Models Of Transport Mechanismmentioning

confidence: 99%

“…Processes 2019, 7, x; doi: FOR PEER REVIEW 4 of 17 (5) The mass transfer resistance of gas within the porous AAO layer is neglected due to its much large pore size [10,26]. (6) Gas mixture (hydrogen and nitrogen) transport through the membrane is under ideal conditions on which the actual separation factor is equal to the ideal selectivity and pure gas permeance is equal to the mixture permeance.…”

Section: Theoretical Models Of Transport Mechanismmentioning

confidence: 99%

Theoretical and Experimental Insights into the Mechanism for Gas Separation through Nanochannels in 2D Laminar MXene Membranes

et al. 2019

View full text Add to dashboard Cite

Clarifying the mechanism for the gas transportation in the emerging 2D materials-based membranes plays an important role on the design and performance optimization. In this work, the corresponding studies were conducted experimentally and theoretically. To this end, we measured the gas permeances of hydrogen and nitrogen from their mixture through the supported MXene lamellar membrane. Knudsen diffusion and molecular sieving through straight and tortuous nanochannels were proposed to elucidate the gas transport mechanism. The average pore diameter of 5.05 Å in straight nanochannels was calculated by linear regression in the Knudsen diffusion model. The activation energy for H2 transport in molecular sieving model was calculated to be 20.54 kJ mol−1. From the model, we can predict that the gas permeance of hydrogen (with smaller kinetic diameter) is contributed from both Knudsen diffusion and molecular sieving mechanism, but the permeance of larger molecular gases like nitrogen is sourced from Knudsen diffusion. The effects of the critical conditions such as temperature, the diffusion pore diameter of structural defects, and the thickness of the prepared MXene lamellar membrane on hydrogen and nitrogen permeance were also investigated to understand the hydrogen permeation difference from Knudsen diffusion and molecular sieving. At room temperature, the total hydrogen permeance was contributed 18% by Knudsen diffusion and 82% by molecular sieving. The modeling results indicate that molecular sieving plays a dominant role in controlling gas selectivity.

show abstract

Operando study of water vapor transport through ultra-thin graphene oxide membranes

Cited by 27 publications

References 50 publications

Swelling Pressures of Graphite Oxide and Graphene Oxide Membranes in Water and Ethanol

Swelling Pressures of Graphite Oxide and Graphene Oxide Membranes in Water and Ethanol

Synchrotron Scattering Methods for Nanomaterials and Soft Matter Research

Theoretical and Experimental Insights into the Mechanism for Gas Separation through Nanochannels in 2D Laminar MXene Membranes

Contact Info

Product

Resources

About