New AIIIBIIIO3 interlanthanide perovskite compounds

Berndt, U.; Maier, D.; Keller, C.

doi:10.1016/s0022-4596(74)80051-4

Cited by 8 publications

(11 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to the previous literature discussed above, perovskite-like NdLuO 3 interlanthanides can be formed as a stable phase [15,16]. In fact, the structural stability and formability of perovskite materials are based on the so-called tolerance factor (t), a criterion proposed by Goldschmidt through the relationship [41]:…”

Section: Resultsmentioning

confidence: 99%

“…The present work focuses the ternary lanthanide oxide NdLuO 3 , firstly studied by Schneider and Roth [14] and again reported by Berndt et al [15] as a new material fifteen years later. Both papers did not presented any x-ray diffraction (XRD) data nor further evidence for their findings, only reporting either a mixture of monoclinic and cubic phases after heat treatments at 1650 C for 6 h [14] or a mixture of 50% of the perovskite phase (orthorhombic) in combination with monoclinic and cubic phases after solid-state reactions of coprecipitated hydroxides at 1250 C [15].…”

Section: Introductionmentioning

confidence: 94%

“…Bharathy et al [12] presented a nice structure map for all known ternary lanthanide oxides in the literature, which shows that NdLuO 3 is known, but its structure has not been reported by X-ray or neutron diffraction techniques. In fact, in their introduction, Barathy et al [12] mentioned NdLuO 3 as studied by Berndt et al [15], Ito et al [3] and Su et al [16]. Unfortunately, Ito et al [3] did not presented any result for this interlanthanide.…”

Section: Introductionmentioning

confidence: 99%

“…Both papers did not presented any x-ray diffraction (XRD) data nor further evidence for their findings, only reporting either a mixture of monoclinic and cubic phases after heat treatments at 1650 C for 6 h [14] or a mixture of 50% of the perovskite phase (orthorhombic) in combination with monoclinic and cubic phases after solid-state reactions of coprecipitated hydroxides at 1250 C [15]. Su et al [16] proposed the synthesis of many ternary lanthanide oxides, including NdLuO 3 , by using for the first time high pressure and high temperature methods.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Structural and vibrational properties of phase-pure monoclinic NdLuO3 interlanthanides synthesized from nanostructured precursors

Soares

Siqueira

Moreira

et al. 2016

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 94%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Structural and vibrational properties of phase-pure monoclinic NdLuO3 interlanthanides synthesized from nanostructured precursors

Soares

Siqueira

Moreira

et al. 2016

Journal of Alloys and Compounds

View full text Add to dashboard Cite

“…Recently, several types of catalyst for OCM reaction have been studied and reported, from which the suitable catalysts for this reaction include SrF2/Nd2O3, Mn/Na2WO4/SiO2, La2O3, LaAlO3, LaCoO3,LaCrO3, BaxSr1-xTiO3, SrTi1-xLixO3 and Au/LSM [8][9][10][11][12][13][14][15][16][17]. Among these catalysts, the use of perovskite material (ABO3) as the catalyst as well as the support for the OCM reaction has been widely reported to enhance the good activity in term of product yield and product selectivity [18][19][20][21][22][23][24][25][26][27]. Importantly, the properties of perovskite material can tolerate a wide variety of composition and constituent elements by the main structure unchanged; hence perovskite material has the possibility to improve the properties by partial substitution of cations and can be used at high temperature conditions.…”

Section: Introductionmentioning

confidence: 99%

Reactivity of Au/La1-xSrxCr1-yNiyO3-δ toward Oxidative Coupling of Methane for C2 and C3 Hydrocarbons Production

Worraphon¹,

Wiyaratn²,

Assabumrungrat³

et al. 2014

View full text Add to dashboard Cite

Abstract. La0.8Sr0.2Cr0.9Ni0.1O3 (LSCN) perovskite was calcined in hydrogen atmosphere (LSCN-H2) that provides better activity than LSCN-air. The doping of Au (as Au/LSCN-H2) improved the catalyst stability toward oxidativecoupling of methane (OCM) reaction by increasing the resistance of carbon formation on catalyst surface during the reaction. The suitable CH4:O2 ratio appeared to be 2:1, from which 5.8%, 29.9%, 8.1%, and 5.8% of C2H4, C2H6, C3H6, and C3H8 can be produced respectively. Importantly, the addition of CO2 can significantly promote the yield of C3H8 produced, from which the suitable CH4:CO2 ratio was observed to be 1:2 (with or without O2 presenting).

show abstract

Phase equilibria in the system HfO2-Y2O3-La2O3 AT 1900°C

Andrievskaya

Lopato

Smirnov

2006

Powder Metall Met Ceram

View full text Add to dashboard Cite

621.762We have used x-ray phase analysis, electron-probe microanalysis, petrography, and electron microscopy on annealed specimens to study phase equilibria in the ternary system HfO 2 − Y 2 O 3 − La 2 O 3 at 1900°C over the entire concentration range. We have plotted the isothermal cross section of the phase diagram for this system at the indicated temperature. We found 23 phase regions. A typical feature of the system is formation of solid solutions based on different crystal modifications . We did not observe new phases in the system. The nature of the phase equilibria in the system is consistent with the high relative thermodynamic stability of lanthanum hafnate (ΔH°L a 2 Hf 2 O 7 ≈ 100 kJ/mole) compared with LaYO 3 . We established that adding a third component extends the thermal stability region for the ordered phase of LaYO 3 toward higher temperatures.Keywords: phase equilibria, hafnium oxide, yttrium oxide, lanthanum oxide, isothermal cross section, solid solution, ordered phase, pyrochlore type phase, phase diagram of a ternary system.The HfO 2 − Y 2 O 3 − La 2 O 3 system is of interest from the standpoint of designing refractory, structural, optical, and other materials that can operate at high temperatures and have unique properties due not only to the features of the original oxides (high melting points, thermodynamic stability, martensitic nature of the series of transformations) but also the effect of complex alloying additives [1][2][3]. The aim of this work was to study the interactions in the HfO 2 − Y 2 O 3 − La 2 O 3 system at 1900°C.We previously studied [4,5] the phase equilibria in the system under consideration at 1250°C and 1600°C, and we made a mathematical prediction of the solid-phase transformations at 1900°C [6,7]. In the literature [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] we find descriptions of the structural characteristics of the limiting binary phase diagrams of the systems HfO . Analysis of the literature data on the limiting two-component systems and the results of a study of the phase equilibria in the ternary system showed that at 1900°C, the phase equilibria in the system will be complex. This is determined to a significant extent by the polymorphism of the starting components and formation of two intermediate phases in the limiting systems: La 2 Hf 2 O 7 (Py) and LaYO 3 (R), crystallizing in a cubic structure of the pyrochlore type and the perovskite type with rhombic distortions.In the La 2 O 3 − Y 2 O 3 system, broad regions of solid solutions are formed based on different crystal modifications of the starting components [8][9][10][11][12][13][14][15]. The temperatures of the polymorphic transformations decrease for La 2 O 3 (X H, H A) with yttrium oxide additives and for Y 2 O 3 (H C) with lanthanum oxide additives. The extent of the regions of solid solutions increases as the temperature increases. About 83 mole% Y 2 O 3 is dissolved in X-La 2 O 3 . The solid solutions based on the H phase of rare earth oxides form a continuous series. Th...

show abstract

New AIIIBIIIO3 interlanthanide perovskite compounds

Cited by 8 publications

References 7 publications

Structural and vibrational properties of phase-pure monoclinic NdLuO3 interlanthanides synthesized from nanostructured precursors

Structural and vibrational properties of phase-pure monoclinic NdLuO3 interlanthanides synthesized from nanostructured precursors

Reactivity of Au/La1-xSrxCr1-yNiyO3-δ toward Oxidative Coupling of Methane for C2 and C3 Hydrocarbons Production

Phase equilibria in the system HfO2-Y2O3-La2O3 AT 1900°C

Contact Info

Product

Resources

About