M.V. Yarmolich, N.A. Kalanda, S.E. Demyanov, L.I. HURSKI, L.V. Kovalev, A.I. Galyas

Doklady Belorusskogo gosudarstvennogo universiteta informatiki i radioèlektroniki

卷:0

L. I. Hurski¹  N. A. Kalanda²  A. I. Galyas²  S. E. Demyanov²  M. V. Yarmolich²  L. V. Kovalev² 

[1] Белорусский государственный университет информатики и радиоэлектроники;

[2] ГО «НПЦ НАН Беларуси по материаловедению»;

关键词: strontium ferromolybdate;    citrate-gel method;    superstructural ordering;    redistribution of the electron density;    magnetization;    superparamagnetic state;   

DOI  :  

来源: DOAJ

【 摘 要 】

Single-phase nanosized Sr2FeMoO6-δ powders were synthesized by citrate-gel method at pH = 4, 6, 9, with various degrees of superstructural ordering of Fe3+ and Mo5+ cations ( P = 65 % for pH = 4, P = 51 % for pH = 6 and P = 20 % for pH = 9). According to the XPS analysis results, mixed valence state of cations iron and molybdenum was established. With increasing of pH, the Fe2+ concentration value rises from 63 % to 72 %, whereas the Fe+3 concentration drops from 37 % to 28 %. According to the results of investigations of magnetization temperature dependence performed in ZFC (zero-field cooling) and FC (field cooling) modes a metastable superparamagnetic state in low-dimensional grains of Sr2FeMoO6-d ferrimagnetic powders at T < 19 K was established. In powders with pH = 4 the number of low dimensional grains is significantly larger than powders with pH = 6 and 9. This has led to their large magnetization value at T = (4,2-19) K.

【 授权许可】

Unknown