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991.
3,4‐Phenylenedioxythiophene (PheDOT) Based Hole‐Transporting Materials for Perovskite Solar Cells
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Jian Chen Bai‐Xue Chen Fang‐Shuai Zhang Hui‐Juan Yu Shuang Ma Prof. Dr. Dai‐Bin Kuang Dr. Guang Shao Prof. Dr. Cheng‐Yong Su 《化学:亚洲杂志》2016,11(7):1043-1049
Two new electron‐rich molecules based on 3,4‐phenylenedioxythiophene (PheDOT) were synthesized and successfully adopted as hole‐transporting materials (HTMs) in perovskite solar cells (PSCs). X‐ray diffraction, absorption spectra, photoluminescence spectra, electrochemical properties, thermal stabilities, hole mobilities, conductivities, and photovoltaic parameters of PSCs based on these two HTMs were compared with each other. By introducing methoxy substituents into the main skeleton, the energy levels of PheDOT‐core HTM were tuned to match with the perovskite, and its hole mobility was also improved (1.33×10?4 cm2 V?1 s?1, being higher than that of spiro‐OMeTAD, 2.34×10?5 cm2 V?1 s?1). The PSC based on MeO‐PheDOT as HTM exhibits a short‐circuit current density (Jsc) of 18.31 mA cm?2, an open‐circuit potential (Voc) of 0.914 V, and a fill factor (FF) of 0.636, yielding an encouraging power conversion efficiency (PCE) of 10.64 % under AM 1.5G illumination. These results give some insight into how the molecular structures of HTMs affect their performances and pave the way for developing high‐efficiency and low‐cost HTMs for PSCs. 相似文献
992.
Improved Electrochromic Performance of Poly(3,4‐ethylenedioxythiophene) by Incorporating a Three‐Dimensionally Ordered Macroporous Structure
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Dr. Hangchuan Zhang Dr. Huiying Qu Dr. Haiming Lv Dr. Shuai Hou Dr. Kun Zhang Prof. Jiupeng Zhao Xingang Li Prof. Endres Frank Prof. Yao Li 《化学:亚洲杂志》2016,11(20):2882-2888
In this paper, three‐dimensionally ordered macroporous (3DOM) poly(3,4‐ethylenedioxythiophene) (PEDOT) films were electropolymerized from an ionic liquid, 1‐butyl‐3‐methylimidazolium hexafluorophosphate ([Bmim]PF6). The electrochromic performances of the 3DOM PEDOT films were studied. The 3DOM films exhibited high transmittance modulation (41.2 % at λ=580 nm), high ionic fast switching speeds (0.7 and 0.7 s for coloration and bleaching, respectively), and enhanced cycling stability relative to that exhibited by the dense PEDOT film. The relationship between the declining behavior of the transmittance modulation and the nanostructure of the film was investigated. A three‐period decay process was proposed to understand the declining behavior. The 3D interconnected macroporous nanostructure is beneficial for fast ion and electron transportation, high ion accessibility, and maintenance of structure integrity, which result in enhanced cycling stability and fast switching speeds. 相似文献
993.
Jian Cui Haining Wang Lanxia Xin Shuai Zhao Guangye Liu 《Journal of Macromolecular Science: Physics》2016,55(7):693-707
Filling poly(vinyl alcohol) (PVA) with clay, typically montmorillonite (MMT), has been proven to be an attractive option to meet the high-performance requirements of PVA-based materials. In previous reports MMT or organophilic MMT (OMMT) were directly used as fillers. As a result, both exfoliated and intercalated MMT structures coexisted in the resultant nanocomposites. However, there is still a large gap between these nanocomposites and ideally designed ones where individual clay nanolayers (CNLs) are expected to be uniformly dispersed in the PVA. With this in mind, an ameliorative solution casting process is proposed here to prepare PVA nanocomposites. For this purpose the CNLs were prepared ahead of time by exfoliation of MMT in water and then used as fillers. Assessment of the dispersion state of the CNLs in PVA revealed that they (≤5.0 wt%) were randomly and uniformly dispersed (down to the level of individual silicate layers) in and formed strong interfacial interactions with the PVA. This resulted in significantly enhanced physical properties of the resultant nanocomposites relative to neat PVA. In particular, a 104.7% increment in the yield stress was achieved with 5.0 wt% CNLs, much larger than the 15–70% increments of previous PVA nanocomposites using MMT or OMMT as fillers. Additionally, excellent optical clarity of the PVA was obtained for the nanocomposites. 相似文献
994.
建立了测定化妆品中辣椒碱等9种热感剂的高效液相色谱法。样品经80%甲醇超声提取后,过滤,以乙腈-0.5%甲酸水溶液为流动相,采用SymmetryShieldTMRP18色谱柱(250 mm × 4.6 mm,5 μm)分离,液相色谱分离,二极管阵列检测器进行检测。在优化实验条件下,9种热感剂的分离度好,专属性高,其质量浓度在0.2 ~ 100 μg/mL范围内与峰面积呈良好线性关系,相关系数(r2)均不小于0.999 5,检出限(LOD)为0.001 0 ~ 0.003 4 mg/kg。以水基类、乳剂类、膏霜类3种阴性样品作为空白基质,9种热感剂在0.004、0.02、1 mg/kg 3种加标水平下的回收率为75.6% ~ 115%,相对标准偏差(RSD)为0.083% ~ 7.0%。该方法专属性强、灵敏度高、准确度好,可用于化妆品中9种热感剂含量的测定。 相似文献
995.
Xiang-Ji Liao Dongdong Pu Li Yuan Jingjing Tong Shuai Xing Dr. Zhen-Long Tu Prof. Jing-Lin Zuo Prof. Wen-Hua Zheng Prof. You-Xuan Zheng 《Angewandte Chemie (International ed. in English)》2023,62(6):e202217045
Chiral boron/nitrogen doped multiple resonance thermally activated delayed fluorescence (MR-TADF) emitters are promising for highly efficient and color-pure circularly polarized organic light-emitting diodes (CP-OLEDs). Herein, we report two pairs of MR-TADF materials (Czp-tBuCzB, Czp-POAB) based on planar chiral paracyclophane with photoluminescence quantum yields of up to 98 %. The enantiomers showed symmetric circularly polarized photoluminescence spectra with dissymmetry factors |gPL| of up to 1.6×10−3 in doped films. Meanwhile, the sky-blue CP-OLEDs with (R/S)-Czp-tBuCzB showed an external quantum efficiency of 32.1 % with the narrowest full-width at half-maximum of 24 nm among the reported CP-OLEDs, while the devices with (R/S)-Czp-POAB displayed the first nearly pure green CP electroluminescence with |gEL| factors at the 10−3 level. These results demonstrate the incorporation of planar chirality into MR-TADF emitter is a reliable strategy for constructing of efficient CP-OLEDs. 相似文献
996.
Shuai Zhang Nan Jiang Jun-Zhao Xiao Prof. Dr. Guo-Qiang Lin Prof. Dr. Liang Yin 《Angewandte Chemie (International ed. in English)》2023,62(40):e202218798
Herein, a copper(I)-catalyzed asymmetric hydrophosphination of 3,3-disubstituted cyclopropenes is reported. It provides a series of phosphine derivatives in high to excellent diastereo- and enantioselectivities. The methodology enjoys broad substrate scope on both 3,3-disubstituted cyclopropenes and diarylphosphines. The high stereoselectivity is attributed to both the high stability of the Cu(I)-(R,R)-QUINOXP* complex in the presence of stoichiometric HPPh2 and the produced phosphines, and the high-performance asymmetric induction of the Cu(I)-(R,R)-QUINOXP* complex. Finally, the method is used for the synthesis of new chiral phosphine-olefin compounds built on a cyclopropane skeleton, one of which serves as a wonderful ligand in Rh-catalyzed asymmetric conjugate addition of phenylboronic acid to various α,β-unsaturated compounds. 相似文献
997.
Xuewen Li Dr. Shuai Yang Minghao Liu Xiubei Yang Prof. Qing Xu Prof. Gaofeng Zeng Prof. Zheng Jiang 《Angewandte Chemie (International ed. in English)》2023,62(30):e202304356
Metal-free covalent organic frameworks (COFs) have been employed to catalyze the oxygen reduction reaction (ORR). To achieve high activity and selectivity, various building blocks containing heteroatoms and groups linked by imine bonds were used to create catalytic COFs. However, the roles of linkages of COFs in ORR have not been investigated. In this work, the catalytic linkage engineering has been employed to modulate the catalytic behaviors. To create single catalytic sites while avoiding other possible catalytic sites, we synthesized COFs from benzene units linked by various bonds, such as imine, amide, azine, and oxazole bonds. Among these COFs, the oxazole-linkage in COFs enables to catalyze the ORR with the highest activity, which achieved a half-wave potential of 0.75 V and a limited current density of 5.5 mA cm−2. Moreover, the oxazole-linked COF achieved a conversion frequency (TOF) value of 0.0133 S−1, which were 1.9, 1.3, and 7.4-times that of azine-, amide- and imine-COFs, respectively. The theoretical calculation showed that the carbon atoms in oxazole linkages facilitated the formation of OOH* and promoted protonation of O* to form the OH*, thus advancing the catalytic activity. This work guides us on which linkages in COFs are suitable for ORR. 相似文献
998.
Dr. Yubo Pang Shuai Chen Dr. Jie Han Prof. Dr. Chengjian Zhu Dr. Chuan-Gang Zhao Prof. Dr. Jin Xie 《Angewandte Chemie (International ed. in English)》2023,62(31):e202306922
Herein, we present a manganese-catalyzed, branched-selective hydroalkenylation of terminal alkynes, under mild conditions through facile installation of a versatile silanol as a removable directing group. With an alkenyl boronic acid as the coupling partner, this reaction produces stereodefined (E,E)-1,3-dienes with high regio-, chemo- and stereoselectivity. The protocol features mild reaction conditions such as room temperature and an air atmosphere, while maintaining excellent functional group compatibility. The resulting 1,3-dienesilanol products serve as versatile building blocks, as the removal of the silanol group allows for the synthesis of both branched terminal 1,3-dienes for downstream coupling reactions, as well as stereoselective construction of linear (E,E)-1,3-dienes and (E,E,E)- or (E,E,Z)-1,3,5-trienes. In addition, a Diels–Alder cycloaddition can smoothly and selectively deliver silicon-containing pentasubstituted cyclohexene derivatives. Mechanistic investigations, in conjunction with DFT calculations, suggest a bimetallic synergistic activation model to account for the observed enhanced catalytic efficiency and good regioselectivity. 相似文献
999.
Hui Yang Dr. Lili Xia Xuanxuan Ye Jiayi Xu Dr. Tianfeng Liu Dr. Linping Wang Assoc. Prof. Shuai Zhang Prof. Wei Feng Prof. Dongshu Du Prof. Yu Chen 《Angewandte Chemie (International ed. in English)》2023,62(26):e202303539
Hypertension, as a leading risk factor for cardiovascular diseases, is associated with oxidative stress and impairment of endogenous antioxidant mechanisms, but there is still a tremendous knowledge gap between hypertension treatment and nanomedicines. Herein, we report a specific nanozyme based on ultrathin two-dimensional (2D) niobium carbide (Nb2C) MXene, termed Nb2C MXenzyme, to fight against hypertension by achieving highly efficient reactive oxygen species elimination and inflammatory factors inhibition. The biocompatible Nb2C MXenzyme displays multiple enzyme-mimicking activities, involving superoxide dismutase, catalase, glutathione peroxidase, and peroxidase, inducing cytoprotective effects by resisting oxidative stress, thereby alleviating inflammatory response and reducing blood pressure, which is systematically demonstrated in a stress-induced hypertension rat model. This strategy not only opens new opportunities for nanozymes to treat hypertension but also expands the potential biomedical applications of 2D MXene nanosystems. 相似文献
1000.
Yang Yang Lijia Liu Shuai Chen Wenjun Yan Haiqing Zhou Xian-Ming Zhang Xiujun Fan 《Angewandte Chemie (International ed. in English)》2023,62(46):e202306896
Developing efficient and robust hydrogen evolution reaction (HER) catalysts for scalable and sustainable hydrogen production through electrochemical water splitting is strategic and challenging. Herein, heterogeneous Mo8O26-NbNxOy supported on N-doped graphene (defined as Mo8O26-NbNxOy/NG) is synthesized by controllable hydrothermal reaction and nitridation process. The O-exposed Mo8O26 clusters covalently confined on NbNxOy nanodomains provide a distinctive interface configuration and appropriate electronic structure, where fully exposed multiple active sites give excellent HER performance beyond commercial Pt/C catalyst in pH-universal electrolytes. Theoretical studies reveal that the Mo8O26-NbNxOy interface with electronic reconstruction affords near-optimal hydrogen adsorption energy and enhanced initial H2O adsorption. Furthermore, the terminal O atoms in Mo8O26 clusters cooperate with Nb atoms to promote the initial H2O adsorption, and subsequently reduce the H2O dissociation energy, accelerating the entire HER kinetics. 相似文献