Mössbauer spectra and superparamagnetism of europium sulfide nanoparticles
Mössbauer spectra and superparamagnetism of europium sulfide nanoparticles
复制标题
硫化铕纳米颗粒的穆斯堡尔谱和超顺磁性
DOI：
10.1088/0022-3727/47/7/075001
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
J. Dickerson
中科院分区：
文献类型：
--
作者：
C. E. Johnson;L. Costa;J. Johnson;D. E. Brown;S. Somarajan;W. He;J. Dickerson
在几个不同温度下测量了硫化铕（EuS）20纳米颗粒中铕 - 151的穆斯堡尔谱。发现样品中含有高达30%的三价铕，这表明纳米结构的表面氧化渗透程度超过了纳米颗粒最外表面约12%的原子位点。在居里温度（\(T_{c}=16.6\)K）以下，由于超顺磁涨落，谱线变宽，平均穆斯堡尔阻塞温度约为16K。在10K以下，谱图在5K时呈现出完全分裂的磁超精细结构，有效场为29.9T。将这些谱图与块状铁磁性硫化铕的谱图进行了比较。这种方法为氧敏感的纳米材料的成分提供了大量信息。
Mössbauer spectra of 151Eu in 20 nm nanoparticles of EuS were measured at several temperatures. The samples were found to contain up to 30% of Eu3+, which suggests that surface oxidation of the nanostructures penetrated farther than the ∼12% of atomic sites on the outermost surface of the nanoparticles. Below the Curie temperature, Tc = 16.6 K, the spectra showed line broadening due to superparamagnetic fluctuations with an average Mössbauer blocking temperature of about 16 K. Below 10 K, the spectrum became a fully split magnetic hyperfine pattern with an effective field of 29.9 T at 5 K. The spectra were compared with those of bulk ferromagnetic EuS. This approach provides considerable information about the composition of oxygen-sensitive nanoscale materials.
影响因子：
15
作者：
Selinsky, Rachel S.;Han, Jae Hyo;Perez, Elvin A. Morales;Guzei, Ilia A.;Jin, Song
通讯作者：
Jin, Song