Failure Modes of Thin Supported Membranes

Hendriksen, Peter Vang; Høgsberg, Jan Becker; Kjeldsen, Ane Mette; Sørensen, Bent F.; Pedersen, Henrik Guldberg

doi:10.1002/9780470291337.ch34

Cited by 11 publications

(14 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since the temperature required to densify the LCCN/10Sc1YSZ membrane was higher than expected (>1400 °C), and the membrane supports are quite dense and more than strong enough at 1400 °C, higher amounts of pore formers than 61.5 and 64.3 vol % could be considered to retain high gas permeability too after sintering at >>1400 °C. The strength of our 3YSZ tubes ( Table 2) is similar to previously reported planar 3YSZ porous supports (~150 MPa at 45% porosity and ~100 MPa at 55% porosity) [19], twice as strong as porous MgO tubes (82 MPa at 42% porosity) [33], and more than four times as strong as porous BSCF tubes (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36) MPa at 41% porosity) [6]. The gas permeability of the 3YSZ tubes is at the same time improved by an order of magnitude compared to those of MgO (4.7 × 10 −16 m 2 ) at similar porosity (42%) [33].…”

Section: Ceramic Processing Of 3ysz Porous Support Tubessupporting

confidence: 87%

“…To avoid cracking, experiments to reduce the membrane thickness and number of layers were carried out. It was expected that thinner layers hold less energy and have a higher tolerance for strain mismatches [32]. Figure 6 shows how the kind of fracture appears to be related to the membrane thickness.…”

Section: Co-sintering Of Membrane and Activation Layers On The Porousmentioning

confidence: 99%

See 1 more Smart Citation

Exploring the Processing of Tubular Chromite- and Zirconia-Based Oxygen Transport Membranes

et al. 2018

View full text Add to dashboard Cite

Tubular oxygen transport membranes (OTMs) that can be directly integrated in high temperature processes have a large potential to reduce CO 2 emissions. However , the challenging processing of these multilayered tubes, combined with strict material stability requirements, has so far hindered such a direct integration. We have investigated if a porous support based on (Y 2 O 3 ) 0.03 (ZrO 2 ) 0.97 (3YSZ) with a dense composite oxygen membrane consisting of (Y 2 O 3 ) 0.01 (Sc 2 O 3 ) 0.10 (ZrO 2 ) 0.89 (10Sc1YSZ) as an ionic conductor and LaCr 0.85 Cu 0.10 Ni 0.05 O 3−δ (LCCN) as an electronic conductor could be fabricated as a tubular component, since these materials would provide outstanding chemical and mechanical stability. Tubular components were made by extrusion, dip coating, and co-sintering, and their chemical and mechanical integrity was evaluated. Sufficient gas permeability (≥10 −14 m 2 ) and mechanical strength (≥50 MPa) were achieved with extruded 3YSZ porous support tubes. The high co-sintering temperature required to densify the 10ScYSZ/LCCN membrane on the porous support, however, causes challenges related to the evaporation of chromium from the membrane. This chemical degradation caused loss of the LCCN electronic conducting phase and the formation of secondary lanthanum zirconate compounds and fractures. LCCN is therefore not suitable as the electronic conductor in a tubular OTM, unless means to lower the sintering temperature and reduce the chromium evaporation are found that are applicable to the large-scale fabrication of tubular components.

show abstract

Section: Ceramic Processing Of 3ysz Porous Support Tubessupporting

confidence: 87%

Section: Co-sintering Of Membrane and Activation Layers On The Porousmentioning

confidence: 99%

Exploring the Processing of Tubular Chromite- and Zirconia-Based Oxygen Transport Membranes

et al. 2018

View full text Add to dashboard Cite

show abstract

“…A discussion of the consequence of chemical strain in supported membrane architectures can be found in Ref. [60][61][62][63]. …”

mentioning

confidence: 99%

Ionic/Electronic Conductivity, Thermal/Chemical Expansion and Oxygen Permeation in Pr and Gd Co-Doped Ceria Pr_xGd_0.1Ce_0.9-xO_1.95-δ

Cheng

Chatzichristodoulou

Søgaard

et al. 2017

J. Electrochem. Soc.

View full text Add to dashboard Cite

The oxygen permeation flux of Ce 0.9 Gd 0.1 O 1.95-δ (CGO)-based oxygen transport membranes under oxidizing conditions is limited by the electronic conductivity of the material. This work aims to enhance the bulk ambipolar conductivity of CGO by partial substitution of Ce with the redox active element Pr. A series of compositions of Pr x Gd 0.1 Ce 0.9-x O 1.95-δ (x = 0, 0.02, 0.05, 0.08, 0.15, 0.25, 0.3 and 0.4) was prepared by solid state reaction. X-ray powder diffraction (XPD) indicates that Pr is completely dissolved in the fluorite structure up to 40 at.%. Pronounced nonlinear thermal expansion behavior was observed as a function of temperature, due to the simultaneous contributions of both thermal and chemical expansion. The electronic and ionic conductivities were measured as a function of temperature and oxygen partial pressure. Within the range from 10 to 15 at.% Pr, a drastic drop of the activation energy of the hole mobility and an abrupt increase of the hole conductivity at low temperature was observed. The behavior could be rationalized by a simple percolation model. Oxygen permeation fluxes through disk shaped samples fed with air on one side and N 2 on the other side were also measured. The oxygen flux through Pr 0.05 Gd 0.1 Ce 0.85 O 1.95-δ was higher than that for CGO by one order of magnitude owing to the enhanced electronic conductivity albeit the flux is still limited by the electronic conductivity. In terms of the electronic and ionic conductivity, the estimated maximum oxygen permeation flux of a 10 μm Pr 0.4 Gd 0.1 Ce 0.9 O 1.95-δ -based membrane exceeds 10 Nml cm −2 min −1 at 900 • C under a small oxygen potential gradient (0.21/10 −3 bar) which is promising for use in oxygen production and in oxy-fuel combustion. Also the material may be well applicable to SOFC/SOEC composite electrodes where mixed conductivity is also desirable. Dense ceramic oxygen transport membranes (OTMs) could potentially be applied for production of high purity oxygen for medical purposes, supply of oxygen in the steel industry, oxy-fuel combustion schemes, as well as in the cement and glass industries. Also, importantly, OTMs can beneficially be integrated with a biomass gasifier, allowing production of syngas (CO and H 2 ), which is a precursor for a variety of high value chemicals. 1 Besides being applicable for OTMs, 2 acceptor doped-ceria has been intensively studied for use in a number of other applications e.g. solid oxide fuel cells (SOFCs), 3 solid oxide electrolysis cells (SOECs) 4 and for electrocatalysis. 5 In particular, acceptor doped ceria (e.g. CGO) is interesting owing to high oxide ion conductivity (0.12 Scm −1 for Gd 0.1 Ce 0.9 O 1.95-δ at 900• C 6 ), appreciable electrocatalytic activity, high electronic conductivity under reducing conditions, and excellent chemical stability under harsh reducing and even corrosive gaseous conditions. 3,7 Kaiser et al. 8 reported that the oxygen permeation flux of a 27 μm asymmetric 10 at.% Gd-doped ceria-based membrane exceeds 10 ml cm −2 min −1 under a gradie...

show abstract

“…Although the TEC of Pt is quite low (∼9 * 10 −6 K −1 ) [45] compared to other metals, the difference from the TEC of KNNLTM is probably more than 1 * 10 −6 K −1 (the TEC of KNN is ∼7 * 10 −6 K −1 ) [46]. In our system, the stresses due to sintering or TEC mismatches might be somewhat alleviated by the porosity (decreasing stiffness and thus increasing crack resistance) [47] and the low layer thickness (decreasing the total energy) of the Pt layer [48]. Still, the TEC mismatch or sintering stress could be the origin of the minor delaminations between Pt and KNNLTM observed if the support layer thickness was increased.…”

Section: Fabrication Of Multilayered Knnltm Transducersmentioning

confidence: 79%

Textured multilayered piezoelectric structures for energy conversion

2019

View full text Add to dashboard Cite

Piezoelectric materials are essential for the conversion between mechanical and electrical energy, for example in ultrasound imaging and vibrational energy harvesting. Here, we are making and exploring the effects of a new design: co-sintered multilayers with texture (grains of a preferential crystallographic direction). The motivation is the combination of increased piezoelectric response in certain crystallographic directions; multilayer structures where thick films rather than bulk materials can allow higher frequency operation and large area; and co-sintering to avoid detrimental effects from gluing layers together. Samples of the lead-free piezoelectric material Li 0.06 (K 0.52 Na 0.48 ) 0.94 Nb 0.71 Ta 0.29 O 3 with 0.25 mol% Mn (KNNLTM) were made by tape casting and co-sintering. NaNbO 3 platelets with (100) orientation which were used as templates to introduce texture, and polymethyl methacrylate (PMMA) was used as a pore forming agent for making porous substrates. The electrical impedances of the co-sintered samples were recorded and analyzed by equivalent electrical circuit modelling. A texture up to 85% in the [100] crystallographic direction was obtained. The samples displayed ferro-and piezoelectricity, with a maximum thickness coupling coefficient (k t =0.18) between mechanical and electrical energy in the most textured sample. This demonstrates that the introduction of texture in multilayered, co-sintered piezoelectrics shows promise for improving devices for ultrasound imaging or energy harvesting.

show abstract

Failure Modes of Thin Supported Membranes

Cited by 11 publications

References 14 publications

Exploring the Processing of Tubular Chromite- and Zirconia-Based Oxygen Transport Membranes

Exploring the Processing of Tubular Chromite- and Zirconia-Based Oxygen Transport Membranes

Ionic/Electronic Conductivity, Thermal/Chemical Expansion and Oxygen Permeation in Pr and Gd Co-Doped Ceria Pr_xGd_0.1Ce_0.9-xO_1.95-δ

Textured multilayered piezoelectric structures for energy conversion

Contact Info

Product

Resources

About

Failure Modes of Thin Supported Membranes

Cited by 11 publications

References 14 publications

Exploring the Processing of Tubular Chromite- and Zirconia-Based Oxygen Transport Membranes

Exploring the Processing of Tubular Chromite- and Zirconia-Based Oxygen Transport Membranes

Ionic/Electronic Conductivity, Thermal/Chemical Expansion and Oxygen Permeation in Pr and Gd Co-Doped Ceria PrxGd0.1Ce0.9-xO1.95-δ

Textured multilayered piezoelectric structures for energy conversion

Contact Info

Product

Resources

About

Ionic/Electronic Conductivity, Thermal/Chemical Expansion and Oxygen Permeation in Pr and Gd Co-Doped Ceria Pr_xGd_0.1Ce_0.9-xO_1.95-δ