Mechanism of Gas Separation through Amorphous Silicon Oxycarbide Membranes

Prasad, Ravi Mohan; Jüttke, Yvonne; Richter, Hannes; Voigt, Ingolf; Riedel, Ralf; Gurlo, Aleksander

doi:10.1002/adem.201500380

Cited by 18 publications

(16 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…10 and 320, respectively). The experimental gas permeance data were rationalized using solid‐state diffusion (as for He and H 2 ) and gas translational diffusion (for CO 2 and SF 6 ) mechanisms . It was found that microporous SiOC membranes possess higher permeance for hydrogen than that reported for silica membranes.…”

Section: Properties Of Siocmentioning

confidence: 99%

Silicon oxycarbide glasses and glass‐ceramics: “All‐Rounder” materials for advanced structural and functional applications

et al. 2018

Self Cite

View full text Add to dashboard Cite

Silicon oxycarbides can be considered as being carbon‐containing silicates consisting of glass networks in which oxygen and carbon share bonds with silicon. The carbon‐for‐oxygen substitution in silicate glass networks has been shown to induce significant changes in the network connectivity and consequently strong improvements in the properties of the silicate glass network. For instance, SiOC glasses exhibit Young's moduli, hardness values, glass transition, and crystallization temperatures which are superior to those of vitreous silica. Moreover, the silicon oxycarbide glass network exhibits unique structural features such as reduced mass fractal dimension and nano‐heterogeneity, which significantly affect and/or dictate its properties and behavior. In the present Review, a consideration of the current state of the art concerning the synthesis, processing, and various structural and functional properties of silicon‐oxycarbide‐based glasses and glass‐ceramics is done. Thus, the synthesis of silicon oxycarbides starting from macromolecular precursors such as polysiloxanes or alkoxysilanes‐based sol‐gel systems as well as current advances related to their processing will be critically reviewed. In addition, various structural and functional properties of silicon oxycarbides are presented. Specific emphasis will be put on the intimate correlation between the molecular architecture of the precursors and the structural features and properties of the resulting silicon oxycarbides.

show abstract

Section: Properties Of Siocmentioning

confidence: 99%

Silicon oxycarbide glasses and glass‐ceramics: “All‐Rounder” materials for advanced structural and functional applications

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…

…”

mentioning

confidence: 99%

Manufacture of Highly Porous Tubular Alumina Substrates with Anisotropic Pore Structure by Freeze‐Casting

et al. 2020

View full text Add to dashboard Cite

Porous substrates play a major role in devices requiring the flow of fluids such as in filters and membranes. Porous substrates are also extensively used for the preparation of inorganic membranes for microfiltration, [1][2][3] desalination, [4][5][6][7] gas separation, [8][9][10][11] and percrystallization processes. [12,13] These inorganic membranes are known as asymmetric membranes as they are conventionally prepared by coating ceramic [14][15][16] or carbon [17][18][19] thin films as top layers on porous substrates. The importance of the porous substrate is to provide the mechanical strength otherwise not available in thin films. Many inorganic materials such as ceramics [20][21][22] and stainless steel [23][24][25] have been manufactured as porous substrates, though alumina is the most used material due to lower costs and processing versatility. Porous substrates come in several geometries such as tubes, [14,[26][27][28] hollow fibers, [29][30][31] and flat surfaces. [19,32] Traditionally, inorganic porous substrates are prepared from conventional ceramic processes such as slip-casting, [33,34] extrusion, [35,36] dry pressing, [37] tapecasting, [38][39][40] and phase inversion hollow fibers. [41,42] A relatively more recent method is the freeze-casting technique for processing porous ceramic substrates. [43][44][45][46] Due to the ability of forming an aligned pore structure, this technique can overcome problems associated with lower fluid fluxes conferred by conventional ceramic processing methods such as tortuous pore structure, constrictions, and dead-end and isolated pores. [47] Freeze-cast starts with the preparation of a stable ceramic suspension (or slurry) at normal conditions followed by controlled freezing of the solvent of the ceramic

show abstract

“…The membrane thickness (L) was 50 nm as obtained from the SEM image shown in Fig. 2 and jump distance (d) was 0.8 nm which was used by following previous reports [39,45]. The calculated permeances of He and H2 were well consistent with experimental data, so that the solid-state diffusion model fitting analysis was to be made appropriately.…”

Section: Analysis Of Gas Permeation Behaviors (1) He and H2 Permeationsmentioning

confidence: 77%

“…The fitting parameters obtained in this study were listed in Table 2, and compared with those for H2-selective amorphous ceramic membranes previously reported by other research groups: polysiloxanederived amorphous silicon oxycarbide (SiOC) membrane (#01) synthesized by pyrolysis at 700 • C in Ar [45], and CVD-derived SiO2 membranes (#02 ~ 05) having different microporosity which Oyama et al [41,42,46,47] systematically synthesized by varying the organic ligand of starting Si alkoxide precursor and CVD process temperature in Ar: #02 [46] and #03 [41] (tetraethoxysilane (TEOS) at 600 • C), #04 (vinyltriethoxysilane (VTES) at 600 • C) [42], #05 (35% trimethylmethoxysilane (TMMOS) -TEOS at 650 • C) [47].…”

Section: Analysis Of Gas Permeation Behaviors (1) He and H2 Permeationsmentioning

confidence: 87%

Superhydrophobic polycarbosilane membranes for purification of solar hydrogen

Kubo

Okibayashi

Kojima

et al. 2021

Separation and Purification Technology

View full text Add to dashboard Cite

Superhydrophobic membranes composed of an organic-inorganic hybrid polymer, namely polycarbosilane (PCS) with Mw of 4-8.9 ×10 3 , were formed on a mesoporous γ-Al 2O3-modified α-Al2O3 porous support. Under dry condition at 50 • C, the supported PCS membranes exhibited H2 permeance of 1.1-1.6 ×10 −6 mol⋅m −2 ⋅s −1 ⋅Pa −1 and H2/N2 selectivity of 9.7-12.6 together with unique H2/He selectivity of 1.4-1.6. Even under saturated humidity at 50 • C, H2 permeance remained at 7.7 ×10 −8 mol −1 m −2 s −1 Pa −1 with improved H2/N2 selectivity of 26. Moreover, when the measurements were performed using a H2-N2 (2:1) mixed feed gas as a simulated syngas produced by novel solar hydrogen production systems, the H2 permeance almost unchanged, while the N2 permeance was below the limit of detection. These results revealed a great potential of PCSs to develop novel H 2selective membranes for purifying solar hydrogen under high-humidity conditions around 50 • C. Further study on the gas permeation behaviors of He, H2 and N2 suggested that the enhanced H2/N2 selectivity under the highhumidity conditions could be explained by the synergistic effect of preferential H 2 permeation through the dense PCS network governed by the solid state diffusion mechanism and blockage of N 2 permeation through micropore channels within the PCS network by the permeate H2O-induced plugging at around the hetero interface between the superhydrophobic PCS and highly hydrophilic γ-Al 2O3.

show abstract

Mechanism of Gas Separation through Amorphous Silicon Oxycarbide Membranes

Cited by 18 publications

References 52 publications

Silicon oxycarbide glasses and glass‐ceramics: “All‐Rounder” materials for advanced structural and functional applications

Silicon oxycarbide glasses and glass‐ceramics: “All‐Rounder” materials for advanced structural and functional applications

Manufacture of Highly Porous Tubular Alumina Substrates with Anisotropic Pore Structure by Freeze‐Casting

Superhydrophobic polycarbosilane membranes for purification of solar hydrogen

Contact Info

Product

Resources

About