Hydrogen permeance of palladium?copper alloy membranes over a wide range of temperatures and pressures

Howard, Bret H.

doi:10.1016/j.memsci.2004.04.031

Cited by 195 publications

(80 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…atomic size, valency & electronegativity. But its crystal structure is, however, different (Fe has bcc structure, while Cu and Pd have fcc structure) [12]. This may be the primary reason for partial solubility or miscibility gap of Fe in Cu-Pd.…”

Section: Resultsmentioning

confidence: 99%

Phase analysis of Cu-Fe-Pd ternary alloys

Ahmad¹,

Ziya²,

Atiq³

et al. 2021

View full text Add to dashboard Cite

X-ray diffraction (XRD) experiments have been carried out to determine the structure and volume fractions of various phases present in Cu-Fe-Pd alloys. The volume percentage of each phase has been determined from integrated intensity of Bragg's peaks. The results can be divided into two parts on the basis of alloy composition. The alloys with 5 at.% Pd contain disordered face centered cubic (fcc) type as a major phase with traces of body centered cubic (bcc) (α-Fe) phase, whereas the alloys with Pd content ranging from 9-20 at.% contain ordered Cu3Au-type phase of Cu-Fe-Pd as a major phase with traces of α-Fe phase. The ordering in various alloys persists up to 1173 K. The results have been explained on the basis of binary phase diagram of Cu-Pd system. K e y w o r d s : crystal structure, metals and alloys, phase transformations

show abstract

Section: Resultsmentioning

confidence: 99%

Phase analysis of Cu-Fe-Pd ternary alloys

Ahmad¹,

Ziya²,

Atiq³

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Despite these difficulties, there is a significant enhancement in the stability temperature limit of the B2 phases in the Mg containing alloy over the binary B2 Cu-48Pd compound. The binary alloy contains two phases (B2+fcc) at room temperature [6]. Increasing the temperature increases the fraction of the fcc Cu(Pd) solid solution.…”

Section: Discussionmentioning

confidence: 99%

“…The critical point of the B2 phase is at 598°C for a composition of 40 at% Pd. It has been shown that Cu-Pd compositions containing ordered bcc (B2) crystal structures exhibit hydrogen permeance comparable to pure palladium [6]. In the Cu-Pd membranes with primarily B2 phase, the superior hydrogen flux increases up to temperatures at which the alloy transforms primarily into a disordered fcc structure where a sharp drop in flux occurs.…”

Section: Introductionmentioning

confidence: 99%

Ordered bcc phases in a Cu–Pd–Mg hydrogen separation membrane alloy

Doğan

Song

et al. 2012

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Surface poisoning and corrosion are shown to be the most significant degradation mechanisms acting on the hydrogen membrane materials at elevated temperatures in synthesis gas derived from coal. Among other metallic dense membrane materials, Cu-Pd alloys have demonstrated promise for being resistant against these degradation mechanisms. Also, it has been shown that Cu-Pd compositions containing ordered bcc (B2) crystal structure exhibit high hydrogen permeability. Magnesium was one of the elements that were found to extend the stability of the B2 phase field in Cu-Pd to higher temperatures. High-temperature XRD, SEM and TEM were utilized to characterize the structure of a Cu-43Pd-5.6Mg (in atomic percent) alloy. Two ordered phases with the same crystal structure (B2), but with different chemical compositions, were identified in the alloy. Transition temperature from these ordered bcc phases to the disordered fcc phase was significantly increased by addition of Mg compared to the binary Cu-48Pd alloy.

show abstract

“…When an appropriate 'temporary' substrate is usedpolymers or silicon, for example -the deposited metal film can easily be peeled from it [16]. The term 'free-standing' is somewhat of a misnomer; permeability measurements are often performed at differential pressures that could damage thin samples, so the foils are usually supported by a porous mechanical backstop [16][17][18]. Electroless deposition, based on autocatalyzed reduction of metal complexes in solution, has been widely applied to formation of alloy functional layers in composite structures [8,10,15].…”

Section: Preparing the Membrane Samplementioning

confidence: 99%

“…The disc is clamped in a fixture that provides physical support (in the case of a freestanding sample) and eliminates leak paths around the edge of the sample [16][17][18]. Care needs to be taken to avoid interdiffusion of the membrane with metallic components of the fixture.…”

Section: Preparing the Membrane Samplementioning

confidence: 99%