Proton Conductivity in Mixed B-Site Doped Perovskite Oxide BaZr[sub 0.5]In[sub 0.25]Yb[sub 0.25]O[sub 3 - delta]
Artikel i vetenskaplig tidskrift, 2010

A wet chemical route was used to prepare the oxygen deficient codoped perovskite oxide BaZr0.5In0.25Yb0.25O3−. Analysis of X-ray powder diffraction data showed that the sample belongs to the cubic crystal system with space group Pmm. Dynamic thermogravimetric (TG) analysis confirmed complete filling of oxygen vacancies (V) by protonic defects (OH) during the hydration process. The proton conductivity was investigated by impedance spectroscopy. The bulk and total conductivities of prehydrated BaZr0.5In0.25Yb0.25O3− were found to be 8.5×10−4 and 2.2×10−5 S cm−1, respectively, at 300°C. The total conductivity in the codoped perovskite oxide was higher compared to that of the respective single doped perovskite oxides with the same doping level. The bulk and grain-boundary mobility and diffusion coefficients of protons were calculated at 200°C using impedance and TG data to obtain the conductivity and proton concentration, respectively. The high bulk diffusivity (2.3×10−7 cm2 s−1) was obtained which indicates that the protons are more free to move in the heavily doped matrix compared to the lightly doped systems where trapping of protons occurs.

barium compounds

X-ray diffraction

zirconium compounds

proton exchange membrane fuel cells

vacancies (crystal)

thermal analysis

Författare

Istaq Ahmed

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

FRANCIS GACHAO KINYANJUI

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Seikh Mohammad Habibur Rahman

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Patrick Steegstra

Göteborgs universitet

Sten Eriksson

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Elisabet Ahlberg

Göteborgs universitet

Journal of the Electrochemical Society

0013-4651 (ISSN)

Vol. 157 12 B1819-B1824

Ämneskategorier

Annan materialteknik

Kemi

DOI

10.1149/1.3494119