The structural stability of the ferromagnetic and metallic double perovskites such as Sr2FeMoO6 has been explored using X-ray diffraction and Raman spectroscopy. It is found that under air atmosphere, at room temperature, the unit cell expands with time and gradually decomposes into SrMoO4. At higher temperatures the decomposition proceeds faster. Whereas in sintered pellets, the effect of this structural transformation on the transport properties is moderate, it becomes dramatic on granular thick films prepared by screen printing. The relevance of these findings for possible technological applications of Sr2FeMoO6 is discussed. (C) 2003 Elsevier Ltd. All rights reserved.
Mixed Oxides as Highly Selective Catalysts for the Flash Pyrolysis of Phenacyl Benzotriazole: One-Pot Synthesis of Dibenzazepin-7-one
摘要:
The one-pot synthesis of dibenzo[b,d]azepin-7-one (3) was selectively achieved from 1-phenacyl-1,2,3-benzotriazole (1) using the catalytic flash vacuum pyrolysis (cfvp) methodology. Catalysts with the scheelite structure ABO(4) (A = Ca2+, Sr2+, Ba2+ and B = Mo6+, W6+) and fergusonite BiVO4 were explored in this new catalytic reaction. These oxides promoted high conversion of starting material at lower temperatures than those observed for noncatalytic reactions. The chemical nature of A and B cations in the scheelite structure showed a strong influence on the formation toward the desired azepinone. In addition, the catalyst's morphology had a significant influence on the course of the cfvp reaction.
Chromium–doped MoS2 “inorganic fullerene” nanoparticles prepared by topotactic reaction from oxosalt precursor
作者:Camella Oumahi、Pavel Afanasiev
DOI:10.1016/j.jallcom.2018.07.312
日期:2018.11
Abstract Hollow sulfides nanoparticles of MoS2, Cr2S3 and Mo0.9Cr0.1S2 (“inorganic fullerenes”) were prepared from SrMo(Cr)O4 precursors by means of a topotactic solid-gas reaction with H2S/CCl4 mixture. The obtained hollow sulfide nanoparticles have narrow size distributions and high specific surface areas. In the Mo-Cr doped sulfide material, chromium is homogeneously distributed substituting molybdenum
Solvothermal Morphology Studies: Alkali and Alkaline Earth Molybdates
作者:Alexej Michailovski、Frank Krumeich、Greta R. Patzke
DOI:10.1002/hlca.200490095
日期:2004.5
A convenient and systematic solvothermal pathway towards alkali and alkaline-earth molybdates has been established. The solvothermal treatment of a molybdenum-based precursor material (yellow molybdic acid, MoO3⋅2 H2O) with ionic additives (alkali or alkaline-earth halides) provides access to a spectrum of molybdates. Their particle morphology can further be addressed by optimizing the reaction conditions
The photocatalytic performance for Mn‐doping SrMoO
<sub>4</sub>
reduced in H
<sub>2</sub>
/N
<sub>2</sub>
mixture atmospheres
作者:Yong‐Lai Liu、Zhen‐Xiang Dai、Zi‐Feng Yao、Gan‐Hong Zheng、Yong‐Qing Ma
DOI:10.1002/aoc.5745
日期:2020.9
visible light photocatalytic activity. The methyl blue (MB) solution was degraded, and the degradation efficiency was 80.30% in 120 min for SMO700 sample. For the 2%Mndoping SrMoO4 sample, the efficiency of degradation reached 97.53% when the annealing temperature was 700 °C(2Mn‐SMO700). The results showed that a certain amount of SrMoO3 is helpful to improve the photocatalyticperformance of SrMoO4.
SrMoO 4和Mn掺杂的SrMoO 4纳米粒子是通过金属有机盐在高沸点的有机溶剂中高温热分解而合成的。然后在不同的还原温度T R下在H 2 / N 2混合气氛中将它们还原。样品通过X射线衍射(XRD),紫外可见光谱(UV)和X射线光电子能谱(XPS)进行表征。XRD和XPS结果表明SrMoO 3当退火温度为700°C(SMO700)时出现相。光吸收边缘移至可见光范围并增强了可见光的光催化活性。甲基蓝(MB)溶液被降解,SMO700样品在120分钟内的降解效率为80.30%。对于2%Mn掺杂SrMoO 4样品,当退火温度为700°C(2Mn-SMO700)时,降解效率达到97.53%。结果表明,一定量的SrMoO 3有助于改善SrMoO 4的光催化性能。此外,SrMoO 4的光催化性能还与Mn掺杂量,退火温度和H 2 / N 2中的退火时间有关。混合气氛。讨论了相关机制。
Assessment of divergent functional properties of seed-like strontium molybdate for the photocatalysis and electrocatalysis of the postharvest scald inhibitor diphenylamine
electrochemical behavior. UV–visible spectroscopy was used to assess the photon absorption characteristics of SrMoO4, which mostly generates OHradicals for the degradation of DPAH. The rate of photodegradation was demonstrated in terms of irradiation time, pH, catalyst loading, and initial concentration. On the other hand, voltammetry was used to evaluate the electrochemical behavior of SrMoO4. The overall reaction
Sr<sub>2</sub>Fe<sub>1.4</sub>Mn<sub>0.1</sub>Mo<sub>0.5</sub>O<sub>6−δ</sub> perovskite cathode for highly efficient CO<sub>2</sub> electrolysis
作者:Yunan Jiang、Yi Yang、Changrong Xia、Henny J. M. Bouwmeester
DOI:10.1039/c9ta07689a
日期:——
An all-ceramic cermet cathode based on perovskite-oxide Sr2Fe1.4Mn0.1Mo0.5O6−δ and samaria-doped ceria shows unprecedented performance in solid oxide electrolysis of pure CO2.