Pure and Mn-doped La4SrTi5O17 layered perovskite as potential solid oxide fuel cell material: Structure and anodic performance

Synthesis and properties of La0.05Ba0.95Ti1−M O3 (M = Mn, Ce) as anode materials for solid oxide fuel cells

“…The quite high values of R s are explained in part by the low electrical conductivity of the electrode materials, which is higher for the Mn-doped compound and by contact resistance at the different interfaces (e.g., at 900 °C, R s value should be around 0.5 Ω cm 2 considering the only electrolyte contribution). Considering the existence of the MLF limiting process, the electrochemical behavior of pure or doped LBT seems slightly different from what has been described for pure or doped cubic-like LSTs, with generally two contributions observed at high and medium (f c N 1 Hz) frequencies, that correspond to charge transfer and surface diffusion of hydrogen, respectively [38,49]. Nevertheless, for highly Mn-doped cubic-type LSTs, Fu et al [87] described an additional low-frequency contribution (f c b 1 Hz) similar to our case, which they associated to gas conversion impedance.…”

“…The standard Pechini route was used to prepare the x = y =0.05 members of the B-site sub-stoichiometric La 0.05 Ba 0.95 Ti 1 −x/4−y M y O 3 series with M = Mn, Ce, i.e., La 0.05 Ba 0.95 Ti 0.9875 O 3 (LBTss), La 0.05 Ba 0.95 Ti 0.9375 Ce 0.05 O 3 (LBTCss), and La 0.05 Ba 0.95 Ti 0.9375 Mn 0.05 O 3 (LBTMss) [48]. Details concerning the protocol for the gel preparation can be found in the study of Périllat-Merceroz et al [42,49]. The solutions were evaporated on a magnetic stirring plate until obtaining gels that were then dried and pyrolyzed in an oven overnight at 250 °C.…”

“…An ECP®-type (M&C) gas cooler was used to trap most of the water vapor, thus allowing gas analysis by a Varian micro-GC equipped with appropriate columns (molecular sieve 5A and Porapak) and a thermal conductivity detector. Details concerning the catalytic test procedure can be found elsewhere [49].…”

“…Considering their high-frequency range (~10 3 -10 4 Hz), as well as the specific capacity and activation energy values, around 1.10 − 5 F cm −2 and 1 eV, respectively, R HF linear evolution can be indubitably associated to a double layer capacity (charge transfer), most probably at the titanate/BIT interface, as for Sr 0.94 Ti 0.9 Nb 0.1 O 3 [36] or lamellar LST [49]. Whereas literature generally report beneficial effects of Mn or Ce doping on electrochemical behavior [27,38,49,87,88], this is not the case here in LBTs series, the lower R HF value being attributed to nondoped LBTss.…”

Designing Perovskite Oxides for Solid Oxide Fuel Cells

“…Fowler et al have also studied these materials, finding that the La 0.6 Sr 0.4 Cr 0.4 Fe 0.6 O 3-δ composition presents the best performance and highest stability [114]. In recent years, a new generation of anode materials with the double perovskite structure, such as Sr 2 MgMoO 6 (SMMO) [115], PrBaM 2 O 5 (M = Co, Mn) [116,117], and La 4 SrTi 5 O 17 [118] have been developed. These materials have very interesting properties which permit the use of multiple fuels.…”