多酸基光敏剂在染料敏化太阳能电池中的应用

染料敏化太阳能电池(dye-sensitized solar cells,简写为DSSCs)是由Michael Gr覿tzel等开发的第三代光伏电池,它具有低成本、制作简单、光学性能可调、光电转换效率高等优势。其中光敏剂是DSSCs的重要组成部分,通过吸收可见光将电子传递到半导体导带,对整个电池的电子循环至关重要。广泛采用的光敏剂为N719等贵金属配合物,但其价格非常昂贵,很难实现大规模产业化。因此寻找低成本的非贵金属光敏剂是该领域的一项挑战。多金属氧酸盐(简称多酸,Polyoxometalates,简写为POMs)是一类具有纳米尺寸的分子基纳米材料,是分子型无机类半导体材料。多酸的富氧表面可以被活化和修饰,吸收光谱可以覆盖可见区甚至近红外区,具有合适的氧化还原电势,良好的热稳定性和溶解性。近年来,一系列研究表明多酸可以作为光敏剂应用在DSSCs中。本文中,我们以课题组多年来在POMs和太阳能电池领域的研究工作积累以及国内外同行专家的研究工作为基础,对多酸基光敏剂在DSSCs中的应用进行了详细综述。首先我们阐述了DSSCs的研究意义、多酸的简介、多酸的能级测量及调控。之后我们重点综述了多酸作为DSSCs中的光敏剂和共敏剂的研究。最后,我们对多酸基光敏剂在DSSCs领域的发展前景进行了总结和展望。本文有望引起多酸化学、材料化学及新兴交叉学科领域研究者的广泛研究兴趣,并为太阳能电池光敏剂的研究提供新的思路。     

通过氯化铵与水分协同辅助钙钛矿结晶制备高效可印刷介观太阳能电池

<正>钙钛矿半导体材料CH_3NH_3PbX_3(X=Cl,Br,I)具有光吸收强、载流子迁移率高、带隙可调、可溶液加工等特点,是制备太阳能电池的理想材料。在过去几年中钙钛矿太阳能电池获得了飞速发展,其公证光电转换效率已高达22.1%,超过了光伏市场上占主导地位的多晶硅太阳能电池最高公证效率1,显示出良好的发展潜力及应用前景,     

低聚噻吩酸敏化多孔TiO2膜的光电转换性能

自从 Gratzel等 [1 ]于 1991年发现染料敏化的 Ti O2 膜具有良好的光电转换性质以来 ,对染料敏化半导体太阳能电池的研究已成为半导体电化学领域的研究热点 [2～ 4] ,这类电池的光电转换效率不断提高[5,6] .但具有较高转换效率的器件多是采用液体电解质和价格昂贵的联吡啶钌化合物作为染料 ,不利于其实际应用的推广 .采用聚噻吩作为电解质 ,并兼敏化作用组装电池已见报道 [7] .低聚噻吩酸具有一定的电导率 ,其分子连有端基羧酸 ,能有效地与 Ti O2 表面羟基作用而吸附 ,同时它们在可见光区有较好的吸光特性 ,是一种潜在的、具有敏化效应…     

无机材料在有机太阳能电池中的应用

无机材料电子迁移率高、光谱响应范围与太阳光谱匹配,而有机材料价格低廉、合成方法简单、容易制作在基底上,因此在太阳能电池中具有更广阔的应用前景。 目前,阻碍有机太阳能电池发展的主要原因是材料的载流子迁移率低、器件稳定性差、吸收光谱与太阳光谱不匹配,导致光电转换效率较低。 若能将有机、无机材料二者的优点相结合,将可提高有机太阳能电池的能量转换效率。 目前的研究已经取得了一定进展,无机材料在受体层、阴极缓冲层、阳极缓冲层中的应用均不同程度地提高了有机太阳能电池的能量转换效率。 本文综述了目前该领域的研究现状,并对今后的研究提出了展望。     

基于吡嗪空穴传输层的合成及在p-i-n型钙钛矿太阳能电池中的应用

钙钛矿太阳能电池由于具有高的光电转换效率,简单的溶液加工工艺,较低的成本等优势因而拥有广阔的应用前景。有机小分子空穴传输层材料在钙钛矿太阳能电池中扮演着极其重要的角色。在本工作中,我们设计和合成了基于吡嗪为分子中心核,三苯胺为分枝的X型空穴传输层材料PT-TPA。与Si-OMeTPA对比,吡嗪的引入不仅不会影响其结晶性,并且能够改善其电荷转移特性和分子中心共平面性,从而显著提升了PT-TPA的空穴迁移率。在非掺杂的情况之下,基于PT-TPA空穴传输层的p-i-n型钙钛矿太阳能电池展现出17.52%的光电转换效率,与相同条件下基于Si-OMeTPA空穴传输层的器件相比,效率提高了近15%。     

方酸染料在染料敏化太阳能电池及氰离子检测中的应用研究

<正>染料敏化纳米晶二氧化钛太阳能电池制备简单、成本低、光电转换效率高,已成为当前光电转换器件研究的热点之一.但目前还有许多制约染料敏化太阳能电池光电转换效率的问题有待解决.基于目前染料敏化太阳能电池在长波区采光不足的问题,本论文深入研究了在红光区域具有强吸光能力的方酸类染料在染料敏化太阳能电池中的应用,重点考察了方酸染料的结构对其光电转换性质的影响,并开辟了一种协同敏化新技术,还利用方酸染料的β-环糊精包合物实现了水溶液中氰根离子的高选择性检测.具体研究结果如下:     

多功能可交联材料在聚合物太阳能电池中的应用

近年来,可交联材料在有机光电器件领域,尤其是聚合物太阳能电池领域,得到了广泛的应用研究。可交联材料作为活性层中的给体材料或受体材料以及制作有序本体异质结聚合物太阳能电池,可以提高器件的稳定性及光电转化效率。可交联材料应用于聚合物太阳能电池的电子传输层或空穴传输层,可以提高器件的开路电压、转化效率、稳定性等各项性能参数。本文根据可交联材料在聚合物太阳能电池中的功能的不同,详细地描述了可交联材料的官能团种类、处理时间、温度以及引发剂等因素对聚合物太阳能电池光电性能的影响,同时评述了可交联材料应用于聚合物太阳能电池的缓冲层及制作有序本体异质结聚合物太阳能电池的研究进展,最后展望了可交联材料在该领域的发展前景。     

拉氏变换阻抗分析测量CdSe薄膜电极的表面态

在光电化学光能转换的研究中,由于多种因素在半导体/溶液界面形成了各种性质和作用不同的表面态,在界面的电荷和能量转移中起着重要作用,对光电转换性能产生较大的影响。对于多晶半导体——作为具有实用前景和目前深受重视的光电转换材料,由于存在较多的晶格缺陷和晶粒界面,在表面形成了浓度较高的表面态,这些表面态可作为光生电子空穴的复合中心,是造成多晶材料光电转换效率低于单晶材料的主要原因。因此测量和研究半导体/溶液界面的表面态能量分布,性质及作用对研究光电转换过程的机理,特别是对改善多晶半导体的性能都具有直接的重要意义。     

非富勒烯电子受体多尺度分子聚集体

有机太阳能电池的光活性层由p型电子供体和n型电子受体构成.这些有机半导体分子的共轭结构和杂元素使其分子间存在强非共价键作用,易于自组装形成分子聚集体,展现出与单个分子截然不同的光电性能,更决定了太阳能电池光吸收、激子解离和电荷传输等光电转换过程.本文介绍了n型非富勒烯电子受体材料在分子及微纳尺度下的多级聚集体形态,包括强结晶性非富勒烯受体的堆叠、成核、结晶机制与抑制手段,以及弱有序非富勒烯受体无规聚集及有序性提升策略.最后,重点讨论了非富勒烯电子受体纤维化的研究进展及关键技术,并对未来高性能非富勒烯电子受体的结构设计和聚集调控进行了总结和展望.     

宽光谱太阳能电池

太阳能电池的光谱响应特性和光电转换效率与光伏材料的微观能带结构及其宏观组装方式密切相关。无论使用哪种光伏材料,普通单结或单层太阳能电池都只能对部分波段的太阳光进行有效利用。宽光谱研究的目标是要使太阳能电池更好地利用太阳光谱所覆盖的全部波段范围的能量,从而提高太阳能电池光电转换效率。本文从化学角度综述了实现宽光谱太阳能电池的基本方法和当前的研究进展,其中包括叠层太阳能电池、中间带太阳能电池、量子点太阳能电池、热光伏太阳能电池、上转换和下转换、分子基柔性太阳能电池等方法。     

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%.     

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.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.