含偕胺肟基螯合纤维吸附、还原Au^(3+)的研究(Ⅰ)——含偕胺肟基螯合纤维对Au^(3+)的吸附行为

研究了含偕胺肟基螫合纤维对Au^(3+)的吸附特征及影响吸附量的因素。结果表明,含偕胺肟基螫合纤维对Au^(3+)的吸附量极高,而且将所吸附的Au^(3+)还原成单质金;在含Au^(3+)、Cu^(2+)+、Zn^(2+)和Cr^(3+)的溶液中,对Au^(3+)具有相当高的吸附选择性。提高偕胺肟基在螯合纤维中的含量及吸附温度和Au^(3+)的初始浓度等均有利于提高吸附量。

有机杂化锑基主族异金属硫属化物的研究进展

本文综述了有机杂化锑基主族异金属硫属化物的研究进展,对它们的结构和异金属次级结构基元进行了描述、归类和总结;探讨了有机组分分别作为结构导向剂和配体两种角色所起到的不同作用;介绍了这类化合物在离子交换、光催化性能方面的研究;展望了该体系的发展趋势。

Chemical vapor deposition growth of crystal monolayer SnS2 with NaCl-assistant

As an important member of the two-dimensional layers of metal dichalcogenides family, the two-dimensional(2 D)group IV metal chalcogenides(GIVMCs) have been attracting intensive attention. However, the growth of monolayer tin disulfide(SnS2) remains a great challenge contrasted to transition metal dichalcogenides, which have been studied quite maturely. Till date, there have been scant reports on the growth of large-scale and large-size monolayer SnS2. Here, we successfully synthesized monolayer SnS2 crystal on SiO2/Si substrates via NaCl-assisted CVD and the edge can be as long as 80 μm. Optical microscope, Raman spectroscopy, x-ray diffraction, atomic force microscopy(AFM), and energydispersion x-ray(EDX) were performed respectively to investigate the morphology, crystallographic structure, and optical property of the 2 D SnS2 nanosheets. In addition, we discussed the growing mechanism of the NaCl-assisted CVD method.

Growth and properties of wide spectral white light emitting diodes

Wide spectral white light emitting diodes have been designed and grown on a sapphire substrate by using a metal-organic chemical vapor deposition system. Three quantum wells with blue-light-emitting, green-light-emitting and red-light-emitting structures were grown according to the design. The surface morphology of the film was observed by using atomic force microscopy. The films were characterized by their photoluminescence measurements. X-ray diffraction t9/2/9 scan spectroscopy was carried out on the multi-quantum wells. The secondary fringes of the symmetric ω/2θ X-ray diffraction scan peaks indicate that the thicknesses and the alloy compositions of the individual quantum wells are repeatable throughout the active region. The room temperature photoluminescence spectra of the structures indicate that the white light emission of the multi-quantum wells is obtained. The light spectrum covers 400 700 nm, which is almost the whole visible light spectrum.

过渡金属(TM=V,Cr,Mn,Fe,Co,Ni)掺杂GeSe的高温铁磁半导体薄膜

具有高温铁磁性的IV族金属硫族化物磁性半导体薄膜是半导体自旋电子器件所需要的重要材料.本文采用固体源化学气相沉积法制备了一系列过渡金属元素(TM=V,Cr,Mn,Fe,Co和Ni)掺杂GeSe的多晶半导体薄膜样品.磁性测量表明,Mn,Fe和Co掺杂的GeSe薄膜表现出较强的铁磁性,居里温度(TC)分别高达277,255和243 K,而V,Cr和Ni掺杂GeSe的多晶薄膜表现出较弱的铁磁性.磁电输运测量表明,Mn,Fe和Co掺杂GeSe的多晶薄膜具有相对较高的空穴浓度,在300 K下高达~1020cm^(-3).基于实验和计算结果的进一步分析表明,Mn,Fe和Co掺杂GeSe的多晶薄膜中的强铁磁性归因于载流子增强的Ruderman-KittelKasuya-Yosida相互作用.我们的研究结果展示了过渡金属掺杂GeSe的磁性半导体薄膜的丰富多样性,并为相关基础研究和器件应用提供了一个新平台.

第四主族金属硫族化合物二维材料研究进展

第四主族金属硫族化合物具有丰富的晶体结构与组成.理论计算预测这类材料的二维晶体具有优异的热电、铁电、压电等性能.但是,目前这类材料的二维结构与性质研究的实验工作尚未系统展开.本文以这类材料二维结构与性质的关联性为切入点,系统展示了这类材料二维结构的合成进展,总结了其二维尺度上的独特性质,并对这类材料的发展前景及挑战进行了展望.