Novel High-Temperature Proton and Mixed-Proton Electron Conductors for Fuel Cells and H 2 -Separation Membranes

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1 UNIVERSITY OF OSLO Novel High-Temperature Proton and Mixed-Proton Electron Conductors for Fuel Cells and H 2 -Separation Membranes Reidar Haugsrud Dept. of Chemistry, FERMiO, University of Oslo SusEN Seminar, Helsinki, Sept. 22, 2011

2 Technological background - - e H 2 H + O N conductor. H + and e -. conductor.. + H 2 +N 2 Challenges: High protonic conductivity combined with chemical stability High protonic and electronic conductivity combined with high chemical stability Low grain boundary resistance

3 PROJECT - CONSORTIUM UNIVERSITY OF OSLO Novel High-Temperature Proton and Mixed-Proton Electron Conductors for Fuel Cells and H 2 -Separation Membranes

4 PARTNERS background N-INNER UNIVERSITY OF OSLO Prof. Truls Norby FERMiO, Dept. of Chemistry Dr. Nikolaos Bonanos Fuel Cells and Solid State Chemistry Dept. Dr. Wilhelm Meulenberg, Institut für Energieforschung, IEF-1 Synthesis Sample preparation XRD SEM Measurements of concentration and transport of defects TG Permeability Electrical conductivity, IS Ionic transport numbers Further characterization, often in collaboration with others: TEM, XPS, SIMS, ND Prof. Sten Eriksson Dept. of Environmental Inorganic Chemistry Theoretical investigations (simulation) of structure and defects Dr. Yngve Larring Sintef, Energy Conversion and Materials Ph.D candidate: Morten Huse

5 PARTNERS - background UNIVERSITY OF OSLO Prof. Truls Norby FERMiO, Dept. of Chemistry Dr. Nikolaos Bonanos Fuel Cells and Solid State Chemistry Dept. Dr. Wilhelm Meulenberg, Institut für Energieforschung, IEF-1 Prof. Sten Eriksson Dept. of Environmental Inorganic Chemistry Dr. Yngve Larring Sintef, Energy Conversion and Materials Post doc.: Sandrine Ricote

6 PARTNERS - background N-INNER UNIVERSITY OF OSLO Prof. Truls Norby FERMiO, Dept. of Chemistry Dr. Nikolaos Bonanos Fuel Cells and Solid State Chemistry Dept. Dr. Wilhelm Meulenberg, Institut für Energieforschung, IEF-1 Prof. Sten Eriksson Dept. of Environmental Inorganic Chemistry Dr. Yngve Larring Sintef, Energy Conversion and Materials Researcher: Mariya Ivanova

7 PARTNERS - background N-INNER UNIVERSITY OF OSLO Prof. Truls Norby FERMiO, Dept. of Chemistry Dr. Nikolaos Bonanos Fuel Cells and Solid State Chemistry Dept. Dr. Wilhelm Meulenberg, Institut für Energieforschung, IEF-1 Prof. Sten Eriksson Dept. of Environmental Inorganic Chemistry CTH, Environmental Inorganic Chemistry Dr. Yngve Larring Sintef, Energy Conversion and Materials Ph.D candidate: Habibur Rhaman

8 PARTNERS - background UNIVERSITY OF OSLO Prof. Truls Norby FERMiO, Dept. of Chemistry Dr. Nikolaos Bonanos Fuel Cells and Solid State Chemistry Dept. Dr. Wilhelm Meulenberg, Institut für Energieforschung, IEF-1 Prof. Sten Eriksson Dept. of Environmental Inorganic Chemistry Dr. Yngve Larring/Dr M.-L. Fontaine Sintef, Energy Conversion and Materials

9 selected results from the project Lanthanum Nickel Niobate Barium Zirconate Barium Cerium Zirconate Metallic perovskites Barium Cerate Barium Indate Calsium Silicates Rare-earth Niobates Rare-earth Tungstates Rare-earth Cerates Lanthanum Vanadate

10 Total conductivity / S/cm Total conductivity, σ tot / S/cm N-INNER RESULTS LaNbO 4 doping, does it help? C 10-3 ' x x 2 O 5 2Ca La 2Nb Nb vo 7OO 2CaO Nb % Ca doped 10-5 O X H2O(g) v OO 2OH O 10-6 Nominally undoped K/T

11 Acceptor substitution in LaNbO 4 Smootheed 3-D data From XRD: From DFT: Unit Cell Vol (Å 3 ) Ca (%) No simple Vegards law behavior Sr (%) Consequence for defect chemistry: x 5La 2O3 3Nb2O5 4TiO2 10La La 4 4 3O H O(g) Nb x 3O11 2 HNbO4 NbO NbO 4 NbO 2 3NbO / TiO 2Nb NbO4 11 3NbO 4

12 RESULTS Rare-earth Niobates Type of doping Nominal composition LaNb 0.99 Ga 0.01 O 4-δ B-site doping LaNb 0.99 Ge 0.01 O 4-δ LaNb 0.99 In 0.01 O 4-δ LaNb 0.99 Ti 0.01 O 4-δ La 0.99 Ca 0.01 Nb 0.99 Ga 0.01 O 4-δ A- and B-site co-doping (Ca on A-site) La 0.99 Ca 0.01 Nb 0.99 Ge 0.01 O 4-δ La 0.99 Ca 0.01 Nb 0.99 In 0.01 O 4-δ La 0.99 Ca 0.01 Nb 0.99 Ti 0.01 O 4-δ A- and B-site codoping (Ba on A-site) La 0.99 Ba 0.01 Nb 0.99 Ga 0.01 O 4-δ La 0.99 Ba 0.01 Nb 0.99 Ge 0.01 O 4-δ La 0.99 Ba 0.01 Nb 0.99 In 0.01 O 4-δ B-site doping high activation energy for proton conductivity Trapping??

13 RESULTS Rare-earth Niobates / x HNbO TiO x 4 HTiO NbO NbO 4 NbO NbO 4 NbO H,assoc e Z T k V 0 0 x 1/ 2 HTiO S H 2 Hdissoc 1 N 4 NbO4 p exp mob,h k exp mob,h kt 2 2 e Z T k V H S H mob,h mob,h HNbO exp exp 4 NbO k kt Non-associated defects Associated defects

14 Empirical correlations in the LaMO 4 systems Can we learn anything from fitting data?

15 Log( {S. cm -1 }) RESULTS Perovskites N-INNER NiO as sintering aid: sintering temperature reduced to 1450 o C. No effects on conductivity characteristics T (ºC) Direct determination of hydration enthalpies by means of TG-DSC -2.0 P(H 2 O)= atm, fit P(H 2 O)= atm, fit P(H 2 O)= atm, fit P(H 2 O)= atm, fit P(H 2 O)= atm, exp P(H 2 O)=0.0004atm, exp Invaluable empirical data BCZY27-1Ni /T (K -1 ) perovskites, ABO 3 Electronegativity difference

16 RESULTS Perovskites BaTi 0.5 In 0.5 O 3- : Interesting candidate material for PCFC electrolytes Stable under CO 2 and H 2?? Conductivity Relatively low dehydration temperature - may limit proton conductivity

17 RESULTS Rare-earth tungstates, La/W= [ ] t oxide ion t proton t electron Mixed conductor with excellent chemical stability

18 lattice parameter (Å) N-INNER RESULTS Rare-earth tungstates, La/W= [ ] In-situ ND contributes to the understanding of hydration Inherent oxygen deficiency: - an alternative to acceptor doping - complex defect notation undoped lanthanum tunsgtate (La/W=5.6) T ( 0 C) DRY AR / O 54 v O O O H 2O(g) 2OH / v OH O 56 3 W La O O O 56

19 other business.

20 Mobility and joint research efforts

21 Synergies, input towards commercialization, and spin-off projects

22 Synergies, input towards commercialization, and spin-off projects The Norwegian PCFC initiative;

23 Dissemination N-INNER Symposium Publications and presentations: 24 talks at int. gatherings 11 posters at int. conferences 21 peer-reviewed papers approx. 30% with joint authorship 60 scientists came together to present and discuss Solid State Ionics for future energy technologies

24 Habibur Sandrine Acknowledging the N-INNER 2007 initiative Morten Mariya