Bi_2O_2Se纳米带的气-液-固生长与高性能晶体管的构筑（英文）

作为一种具有高迁移率、高空气稳定性和带隙可调的二维材料,纳米硒氧化铋(Bi_2O_2Se)半导体有望成为未来电子学集成器件和光电子集成器件沟道材料的候选半导体。高质量的Bi_2O_2Se纳米带有望用于高性能晶体管的构筑;然而,其一维结构的合成方法尚未开发。在我们的研究中,我们在云母衬底上通过Bi催化汽-液-固生长机制合成了一维Bi_2O_2Se纳米带。合成的Bi_2O_2Se单晶纳米带的宽度为100 nm到20μm,长度可达亚毫米。再者,Bi_2O_2Se纳米带可以很容易地利用洁净转移方法被转移到Si O_2/Si衬底上,并进一步制备成高性能场效应器件。Bi_2O_2Se纳米带场效应器件表现出优异的电学性质:室温电子迁移率高达～220 cm~2·V~(-1)·s~(-1),开关比高达 106,10μm沟道长度下电流密度高达～42μA·μm~(-1)。由此说明,Bi_2O_2Se纳米带有望成为候选材料用于未来高性能晶体管的构筑。     

BiOBr的制备及其光催化性能的研究

以氧化铋为原料,采用水解法合成了溴氧化铋光催化剂,采用X射线衍射仪对溴氧化铋晶体进行表征,研究了溴氧化铋晶体降解罗丹明B溶液的光催化性能。实验结果表明,在反应温度为40℃、反应时间为90 min合成的Bi OBr光催化性能最好,具有较强的光催化活性,其催化活性优于Bi OCl催化剂,其催化降解罗丹明B反应表现为假一级动力学。     

铋系光催化剂去除环境污染物

铋系半导体材料是近年来研究较热的一类新型光催化剂,因其具有独特的层状结构和合适的禁带宽度,而表现出了良好的太阳光催化性能,在环境污染物去除方面展现出极大的潜力。本文综述了近年来铋系光催化剂(氧化铋、硫化铋、钨酸铋、钼酸铋、钒酸铋、卤氧化铋等)在环境污染物去除方面的最新研究进展,介绍了几类常见的铋系半导体材料及其制备方法,归纳和总结了铋系光催化剂在大气净化、有机废水处理、重金属离子处理和杀菌等方面的应用,同时对今后铋系光催化剂在环境污染去除方面的应用进行了展望。     

基于对硝基苯酚还原模型反应的纳米金催化材料

硝基苯酚是工业和农业废水中常见的有机污染物之一。近年来,由于纳米金催化材料的优异催化性能,纳米金催化材料日益成为催化还原对硝基苯酚的一种高效、快速和环境友好的催化材料;合成高度分散、尺寸均一、稳定、易分离及可重复使用的纳米金催化材料是该领域的研究重点。本文以纳米金催化材料的整体结构为主线,归纳了纳米金催化材料的最新研究进展;重点讨论了纳米金催化材料的制备手段及其催化活性、稳定性、可回收性和可重复使用性;并对纳米金催化材料的发展方向和今后需解决的关键问题进行了展望。     

微波加热合成多孔花状结构的纳米α-Bi_2O_3

<正>金属氧化物如氧化钛、氧化锌、氧化铜、氧化铁和氧化铋等是一类重要的半导体材料,它们在磁存储介质、太阳能转换、电子器件和催化等领域里有着广泛的应用,因此其纳米粉体的制备及性能研究吸引了众多的科学工作者。     

无机纳米稀土发光材料的制备方法

无机纳米稀土发光材料作为一种重要的发光材料,由于具有独特的光、电和化学性质,使其在高性能磁体、发光器件、显示、生物标记、光学成像和光学治疗等方面得到了广泛的应用。稀土发光材料的这些性质与材料的尺寸和形状密切相关,近年来研究者已经利用多种合成方法制备了不同形状的纳米稀土发光材料,包括纳米线、纳米棒、纳米管、纳米纤维和纳米片等。本文综述了无机纳米稀土发光材料的几种常用的制备方法,包括水热/溶剂热法、有机/无机前驱体热分解法和超声辅助合成法等,评述了这些方法的优缺点,并结合课题组在无机纳米稀土发光材料制备方面的工作,对无机纳米稀土发光材料制备方法的发展进行了展望。     

锂离子电池纳米负极电极材料

综述了锂离子电池纳米负极材料研究的最新进展,根据材料的化学组成把锂离子电池纳米级负极材料分为金属基纳米负极材料、非金属基纳米负极材料、金属-非金属复合纳米负极材料、纳米氧化物负极材料和其它纳米负极材料。论述了各类材料的优势和存在的问题,探讨了这些材料的主要制备方法与其结构、形貌和电化学性能之间的关系,展望了纳米负极材料用于锂离子电池的前景。     

光催化与现代测试技术应用于物理化学实验的探索——以锑掺杂氧化铋的制备及光催化性能测试为例

以一个掺杂型复合催化剂的制备与催化性能测试为实例,尝试了将光催化和现代测试技术应用于物理化学实验教学。采用溶剂热法合成锑掺杂氧化铋纳米材料,并通过X射线粉末衍射和扫描电子显微镜对其成分和形貌进行表征。选取罗丹明B作为模拟有机污染物,对可见光条件下锑掺杂前后氧化铋纳米材料光催化性能进行评价。结合材料光学性质和光电性质分析探讨锑掺杂提高氧化铋纳米材料光催化性能的机制。通过开设该实验,可让学生获取化学学科的前沿知识,了解光催化反应以及各种现代测试技术的基本原理,掌握新的实验操作技能和数据处理方法,加深对物理化学基础知识的理解,对提高学生的综合实验能力,培养创新型、复合型人才具有重要意义。     

纳米孔生物分子检测研究

纳米孔单分子检测技术是一种集操作简单、灵敏度高、检测速度快、无需标记等优点的传感检测技术,广泛应用于蛋白质检测、基因测序和标志物检测等领域。基因测序的费用、灵敏度和精度是该检测技术的发展中亟待解决的主要问题,而开发新型的纳米孔材料则是解决这些问题的关键手段。本文从纳米孔材料的选择和设计角度出发,综述了三种不同的纳米孔,即蛋白质等生物纳米孔、固态纳米孔和新型二维材料纳米孔在生物分子检测方面的应用现状,并比较了生物纳米孔与固态纳米孔的差别。本文也重点阐述了二维材料纳米孔在生物分子检测中的实验和模拟研究进展。最后,对纳米孔检测技术的发展前景进行了展望。     

纳米晶体材料研究进展

综述了目前纳米晶体材料合成、结构、性质和应用的研究和发展现状。通过惰性气体凝结、机械合金、等离子体技术和其他许多方法可以制得纳米晶体材料。尽管早期的研究者认为纳米晶体材料的晶粒边界结构不同于常规材料, 但目前有关纳米晶体材料结构的研究表明其具有与常规晶体材料相同的晶粒边界结构。纳米晶体材料所具有的诸如扩散和烧结、力学、陶瓷和金属间化合物的延展性、电学、热膨胀、光学、磁学、催化和腐蚀行为等性质优于常规多晶材料, 这些性质具有巨大的潜在应用价值。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.     

Copper-catalyzed multicomponent reactions of 2-iodoanilines,benzylamines, and elemental sulfur toward 2-arylbenzothiazoles

A relatively cheap copper salt-catalyzed, three-component approach providing 2-arylbenzothiazoles in good to excellent yields from readily available 2-iodoanilines, benzylamines, and sulfur powder is reported. This methodology allows preparation of various classes of 2-arylbenzothiazoles and provides a general, reliable approach.