Defect structure and transport properties of Ni-SrCeO{sub 3-delta} cermet for hydrogen separation membrane.

Journal Article · Sat Jan 01 04:00:00 EST 2005 · J. Electrochem. Soc.

DOI:https://doi.org/10.1149/1.2060690· OSTI ID:925234

Song, S -J; Lee, T H; Wachsman, E D; Chen, L; Dorris, S E; Balachandran, U

Research on hydrogen separation membranes is motivated by the increasing demand for an environmentally benign, inexpensive technology for separating hydrogen from gas mixtures. Although most studies of hydrogen separation membranes have focused on proton-conducting oxides by themselves, the addition of metal to these oxides increases their hydrogen permeability and improves their mechanical stability. This study began by determining hydrogen permeation properties of SrCe0.8Yb0.2O3-delta (SCYb). The results showed that at the investigated temperatures (600-900 degrees C), the hydrogen permeation rate is limited by electron flow. To further enhance hydrogen permeability, a cermet (i.e., ceramic-metal composite) membrane was made by adding Ni to the SCYb. At 900 degrees C, with 20% H-2/balance He as a feed gas (p(H2O) = 0.03 atm), the hydrogen permeation rate was 0.105 cm(3)/min cm(2) for 0.25-mm-thick Ni/SCYb and 0.008 cm(3)/min cm(2) for SCYb (0.7-mm thick). The dependence of hydrogen permeability on temperature and hydrogen partial-pressure gradients was also determined. The proton conductivity (approximate to ambipolar conductivity) was extracted from the dependence of hydrogen permeability on hydrogen potential gradients. The results demonstrate that adding Ni to SCYb considerably increases its hydrogen permeability by increasing its electron conductivity.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: FE
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 925234
• Report Number(s): ANL/ET/JA-52999
• Journal Information: J. Electrochem. Soc., Journal Name: J. Electrochem. Soc. Journal Issue: 11 ; 2005 Vol. 112; ISSN JESOAN; ISSN 0013-4651
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

08 HYDROGEN
CERMETS
DEFECTS
ELECTRONS
HYDROGEN
MEMBRANES
MIXTURES
OXIDES
PARTIAL PRESSURE
PERMEABILITY
PROTONS
STABILITY
TRANSPORT