多色高发光效率CsPbX3(X=Cl,Br,I)钙钛矿量子点的制备及其在发光二极管中的应用

采用室温合成法制备出一系列具有高发光效率和多色发光的CsPbX₃钙钛矿量子点(PQDs),反应全过程快速简便,且通过调节不同的卤素组成(Cl,Br,I)可以实现CsPbX₃ PQD的多色发光。 通过表征证明,CsPbX₃ PQDs呈立方晶型,平均粒径约为10 nm,发射光谱覆盖可见光波长范围为410~630 nm,半峰宽14~38 nm,荧光量子产率10%~90%。 最后将CsPbX₃ PQDs应用于发光二极管(LED)器件的制备中,在恒定电压下工作时,能保持LED器件的发光颜色、强度和颜色坐标不变。     

综合创新实验:水溶性荧光防伪墨水YVO4:Eu3+纳米材料的合成与表征*

将科研前沿成果引入到综合化学实验的设计中,设计了面向材料化学专业的创新综合实验:在微波辐射辅助加热的条件下,合成了YVO₄:Eu³⁺纳米材料,并对该材料进行了结构表征。该材料的水相溶胶在紫外光激发下,具有很强的荧光效应,可用作荧光墨水进行特殊图案的打印与书写,其在安全防伪领域具有很大应用潜力。通过材料的实际使用,可加深学生对新材料研究的重视,激发学生的科研兴趣,在培养学生动手实验能力的同时,培养学生创新能力和自主学习能力。     

全无机钙钛矿量子点的疏水改性及LED应用——推荐一个本科生综合化学实验

介绍一个综合化学实验——全无机钙钛矿量子点的疏水改性及LED应用。我们以三甲基氯硅烷和莫来石纤维增强SiO₂气凝胶的疏水性和韧性，获得疏水SiO₂气凝胶，随后以该疏水SiO₂气凝胶吸附全无机钙钛矿量子点形成CsPbX3@SiO₂气凝胶复合材料。通过接触角、红外光谱、X射线衍射等表征手段证实SiO₂气凝胶的成功改性，并制作了LED器件。本实验涉及材料的合成、表征和应用，可作为化学和应用化学专业学生的综合化学实验，有助于提高学生的科学素养，激发对科学研究的兴趣。     

锌-二氧化锰锌离子电池：一个研究型综合性化学实验的设计与实践

面向国家“双碳战略”需求,结合科技前沿和高校学生科研实践,设计了以低成本和高安全性为主要优势的锌-二氧化锰(Zn-MnO₂)二次电池,并形成了一个标准化的物理化学综合实验。本实验首先通过水热法制备了α-MnO₂,采用X射线衍射和扫描电子显微镜对制得α-MnO₂的结构与形貌进行了表征,随后使用电池测试仪对锌片负极与α-MnO₂正极组装成的Zn-MnO₂锌离子电池进行了循环伏安、倍率和循环稳定性等电化学性能测试。该实验将科研热点转化为综合教学实验,从实验室走进日常生活,集化学材料合成、表征与电池电化学性能测试于一体,实验的不同模块可满足多种教学需求。此外,探究式学习与综合性操作相结合有助于提高学生的实验兴趣及化学实验操作水平;在教学过程中融入思政元素,渗透绿色理念,引导学生形成安全无污染的化学实验意识和可持续发展思想。     

CsPbX3(X=Cl,Br,I)纳米晶的制备及其应用

全无机钙钛矿CsPbX₃(X = Cl, Br, I) 纳米晶作为一类新型的低成本直接带隙半导体材料,具有优异的光学性质,如吸收系数高、尺寸和发射波长易调节、半峰宽窄、荧光量子产率高等特性,在照明、能源、信息显示和探测等领域表现出巨大的应用潜力,成为材料领域的研究热点。本文从CsPbX₃纳米晶的结构组成入手,重点综述了其常见的制备方法如高温热注入法、室温再沉淀法、溶剂热法、液滴微流控法、阴离子交换法等,对常见的形貌尺寸控制策略如反应温度和表面配体进行归纳,以及改善CsPbX₃纳米晶稳定性的策略,总结了此类材料在白色发光二极管、电致发光二极管、激光器、光电探测器、太阳能电池等光电领域的应用情况,最后对CsPbX₃纳米晶领域存在的问题和面临的挑战进行了分析和评述。     

磁性纳米Fe3O4制备及在酵母RNA提取分析中的应用

磁珠法提取核酸是新冠病毒核酸检测的关键一环。基于此，以安全无毒的酵母RNA为对象，开发了一个涉及多学科化学知识交叉的综合实验，包括Fe₃O₄纳米磁珠制备与表征、RNA提取方法建立与机制探究、实际样品应用等。本实验既能锻炼学生综合运用化学知识和实验手段解决实际问题的能力，又能引导学生关注公共事件，培养其社会责任感。     

脂质体封端CsPbX3(X=Cl,Br,I)纳米晶体的制备及在发光二极管中的应用

以脂质体充当表面封端配体修饰合成后的CsPbX₃纳米晶体.封端CsPbX₃纳米晶能保持原始形状和粒径大小,相对量子产率提升至（100±3）%,发射光谱在411~626 nm范围内可调.将其存储于空气（温度25℃,相对湿度50%）中150 d仍保持立方晶型.以DOPC-CsPbBr₃为颜色转换器可制造显色指数高达91.2的白色发光二极管,应用前景广阔.     

锑基红色发光薄膜材料的制备与表征——一个复合材料创新型实验

将复合发光薄膜材料研究成果转化为化学和材料类专业的本科实验教学内容，设计了一个复合材料创新型实验——锑基红色发光薄膜材料的制备与表征。以苄基溴、吡啶和氧化锑等为原料，制备了一种五溴合锑酸苄基吡啶季铵盐（[BzPy]₂[SbBr₅]）,再以聚环氧乙烯（PEO）为载体通过静电纺丝技术制成发光薄膜材料PEO@[BzPy]₂[SbBr₅]。运用单晶X-射线衍射仪、红外光谱、激光拉曼光谱、固体紫外-可见漫反射光谱、粉末X-射线衍射仪和荧光光谱等手段对薄膜材料的结构和性能进行了表征。学生通过实验可以了解水热法和复合薄膜材料的制备方法，掌握多种分析测试手段表征薄膜材料的结构与性质的技能，激发学习兴趣，锻炼学生科研思维，树立绿色制造理念，提高解决实际问题的能力。     

基于镍纳米团簇-铕混合物的纸基比率荧光传感器检测四环素——推荐一个研究型综合化学实验

介绍了一个科研转化的综合化学实验项目，基于镍纳米团簇(NiNCs)-铕混合物(NiNCs-Eu³⁺)荧光传感器检测四环素。实验包括NiNCs-Eu³⁺的制备、表征及对四环素的响应性能，纸基传感器的构建及可视化识别的分析方法探究。该实验综合性强、操作简便、成本低，有利于培养学生的实验技能和科研探究能力，让学生体验到一个“看得见”的综合化学实验。     

碳布负载氢氧化镍电极材料的合成及其电容性能分析——推荐一个综合化学实验

作为超级电容器的电极材料,Ni(OH)₂具有理论比电容高、来源丰富、环境友好等优点,但较低的电导率影响了其实际性能。解决该问题的一种有效方法是在碳布导电基底上原位生长Ni(OH)₂薄膜。以此为基础设计综合化学实验,通过Ni(OH)₂/碳布薄膜电极的制备、表征及电化学性能测试,使学生进一步理解化学平衡原理在材料合成中的应用,了解材料的基本表征方法,掌握循环伏安法、恒流充放电法等电化学分析方法在实际测试中的运用与解析,从而达到巩固电化学理论知识、培养学生的实验技能、提高学生综合实验能力的目的。本实验的开展还可以帮助学生了解储能领域的科技前沿,激发学生的科研兴趣,培养学生的科研创新意识,适合在大学化学实验中推广应用。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.