Review of perovskite ceramic synthesis and membrane preparation methods

Abstract

In the 25 years since the first report of mixed ionic and electronic conducting ceramics, perovskite membranes underwent both research and development phases, with the latest works entering pilot trials for oxygen separation from air. During this time a number of perovskite synthesis methods were investigated from the original solid state chemistry through the more advanced and well established sol-gel route via the Pechinni method. The advances in synthesis methods were possible due to the desirable full incorporation of cations into the A and B-sites of perovskites with a general ABO 3 structure. In terms of membrane manufacturing, perovskite hollow fibres attracted a major research effort due to small membrane thickness and high fluxes. This led to a number of investigations by doping with other cations or by surface modification, all aiming at increasing oxygen fluxes. Recently, advanced ceramic processing by tape casting has led to the preparation of very thin dense films either on porous supports or as monoliths containing internal porous regions. All these developments in perovskite synthesis and membrane preparation methods, together with other types of methods requiring special equipment are addressed in this review, including an 2 analysis of the state of the art. Finally, future challenges are discussed in terms of competing technologies and potential industrial design directions of perovskite membranes for oxygen separation from air.

Synthesis and Characterization of Lamn1-XFexO3 (X=0, 0.1, 0.2) by Coprecipitation Route

“…LaMnO 3 shows good stability, flexible oxygen stoichiometry (δ) and the different Mn oxidation states i.e., Mn 2+ , Mn 3+ , Mn 4+ , which strongly affects the catalytic behavior. Also, isomorphic substitution of metals in the perovskite structure allows some control the catalytic properties of the material and its several derivatives have been previously investigated [15,16]. Lanthanum-based perovskites containing transition metal in B-site, (LaBO 3 , B=Co, Fe, Ni or Mn), show catalytic activity close to the noble metal, presenting low cost and high thermal stability.…”

Infiltration, Overpotential and Ageing Effects on Cathodes for Solid Oxide Fuel Cells: La0.6Sr0.4Co0.2Fe0.8O3-δversus Ba0.5Sr0.5Co0.8Fe0.2O3-δ

“…3 Their excellent activity for oxygen reduction has been proved widely. [4][5][6][7][8][9][10] Although the structure and electrochemical processes of LSCF and BSCF are quite different, both of them have long-term stability and redox behavior issues to be clarified, in order to be used as cathode materials in commercial devices. Indeed, when used as cathodes in intermediate-temperatures solid oxide fuel cells (IT-SOFCs), they suffer from chemical and structural instability, which causes degradation during operation time.…”

Evaluación del cerámico con estructura tipo perovskita LaFe0,2Co0,8O3 / Evaluation of the perovskite LaFe0.2Co0.8O3

“…Para la síntesis del sistema LaFe 0,2 Co 0,8 O 3 , se partió de disoluciones en concentración 1,00 M de los nitratos de La(NO 3 ) 3 .6H 2 O, Fe(NO 3 ) 3 .9H 2 O, y Co(NO 3 ) 3 .9H 2 O (99,99 %), los cuales se dosificaron en un reactor de vidrio según la composición buscada como ha sido establecido de forma preliminar [15][16][17]. El sistema acuoso, fue tratado tér-micamente a 80 • C bajo condiciones de agitación magnética (150 rpm) y reflujo por 120 minutos; posteriormente, se adicionó al sistema una disolución de ácido cítrico 2,00 M con una proporción 0, 5 : 1 en relación al contenido total de cationes metálicos, para favorecer la formación de compuestos de coordinación tipo citrato, dando continuidad al reflujo por 60 minutos más para asegurar la formación de los respectivos complejos de coordinación entre los cationes componentes y el ligando citrato.…”