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111.
One-dimensional, diluted magnetic semiconductor nanofibers have attracted increasing attention for their unique magnetic properties, large specific surface area, and high porosity. These qualities lead to excellent performance in magneto-optical devices, magnetic resonance imaging, ferrofluids and magnetic separation. The purpose of this study is to fabricate P-type one dimensional CuAlO2-based diluted magnetic semiconductor nanofibers. First, we fabricated Cu Al0.95Co0.05O2 nanofibers with an average diameter of 1 μm with the electrospinning method. The annealed nanofibers were thermally treated at a temperature of 1 100 ℃ and then shrunk to a diameter of about 650 nm. We used X-ray diffraction measurements and Raman spectra to confirm that the Cu Al0.95Co0.05O2 nanofibers had a single impurity free delafossite phase. The X-ray photoelectron spectroscopy analysis indicates that Co was present in the +2 oxidation state, resulting in an room temperature ferromagnetism in the Cu Al0.95Co0.05O2 fiber. This contrasts with nonmagnetism in pristine CuAlO2 fiber. The coercivity(Hc) value of 65.26 Oe and approximate saturation magnetization(Ms) of 0.012 emu/g demonstrate good evidence of ferromagnetism at room temperature for Cu Al0.95Co0.05O2 nanofibers. 相似文献
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Bochkareva N. I. Ivanov A. M. Klochkov A. V. Kogotkov V. S. Rebane Yu. T. Virko M. V. Shreter Y. G. 《Semiconductors》2015,49(6):827-835
Semiconductors - It is shown that the emission efficiency and the 1/f noise level in light-emitting diodes with InGaN/GaN quantum wells correlate with how the differential resistance of a diode... 相似文献
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Zehu Xie Na Peng Tingting Liu Xing Cheng Wuquan Ye Runtian Zheng Jundong Zhang Haoxiang Yu Jie Shu 《Ceramics International》2019,45(9):11812-11818
Here, LiY(WO4)2 nanotubes are prepared via a feasible electrospinning technique. This new anode material shows excellent electrochemical properties. The capacity loss of LiY(WO4)2 nanotubes is as low as 6.9% after 156 cycles, while bulk LiY(WO4)2 presents the capacity loss higher than 55.0%. Even after 600 long-life cycles, the capacity loss of the nanotubes is only 9%. It can be seen that the hollow structure with a rough surface and a porous morphology contributes to the improvement of electrochemical performance. Furthermore, online X-ray diffraction (XRD) method is firstly applied to understand the lithium ions insertion/extraction mechanism of LiY(WO4)2 nanotubes. It can be concluded that it is an asymmetrical two-phase reaction. A phase transformation from LiY(WO4)2 to Li3Y(WO4)2 can be obviously seen from the in situ XRD during discharge process. While Li2Y(WO4)2 appears as an intermediate phase with a reverse charge reaction. In addition, in situ XRD also demonstrates that LiY(WO4)2 nanotubes have surprised electrochemical reversibility. All the above results indicate that LiY(WO4)2 nanotubes can be expected to be anode candidate for rechargeable lithium ion batteries (LIBs). 相似文献
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Semiconductors - We found bulk n-GaAs layers grown by liquid phase epitaxy to be irregularly stressed. Deformation created by this stress causes a small but detectable quadrupole splitting of... 相似文献