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151.
Polyaniline (PANi)-graphene composites and polyaniline-graphene/TiO2 composites were prepared by ex-situ approach. Systematic investigation was carried out to explore photovoltaic (PV) properties of PANi-graphene and PANi-graphene/TiO2 composite. The prepared composites were characterized using X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Raman Spectroscopy and Ultraviolet–Visible (UV–Vis) Spectroscopy. The PV properties of dye-sensitized solar cells (DSSCs) prepared composites investigated by assembling materials in ITO/PANi-graphene/Al and ITO/PANi-graphene/TiO2/Al architecture. Different PV parameters such as short circuit current, open circuit voltage, fill factor and power conversion efficiency were determined from the (Current-Voltage) IV characteristics of PV cell. The 15 wt% PANi loaded graphene composite based PV cell shows optimized power conversion efficiency of the order 6.47%. The main accomplishment of present work is that efficiency associated with 15 wt% PANi loaded graphene composite, improved further by addition of TiO2 nanoparticles. The composite system between PANi-graphene/TiO2 for 1 wt% of TiO2 nanoparticles shows optimized power conversion efficiency of the order 8.63%. 相似文献
152.
有机光伏材料与器件研究的新进展 总被引:4,自引:0,他引:4
近几年有机光伏电池应用研究发展迅猛。本文综述了有机光伏薄膜电池在材料(包括有机小分子材料与聚合物材料)、器件构造方面的最新进展,分析了有机聚合物光伏电池目前效率低的主要原因,并探讨了该领域进一步研究的方向和前景。 相似文献
153.
Photovoltaic devices built by a hierarchical self-assembly process using hydrogen-bonding terminated self-assembled monolayers (SAMs) on gold and the combination of a hydrogen-bonding barbituric acid appended fullerene and a complementary melamine terminated π-conjugated thiophene-based oligomer are presented. The incorporation of these electron donor (oligomer) and electron acceptor (methanofullerene) assemblies into simple photovoltaic (PV) devices as thin films leads to a 2.5 fold-enhancement in photocurrent compared to analogous systems comprising non-hydrogen-bonding C60-oligomer systems, which is ascribed to higher molecular-level ordering. The modification of the gold electrode surface with self-assembled monolayers bearing hydrogen-bonding molecular recognition endgroups was seen to further enhance the PV response of the corresponding functional supramolecular device. This superposition of two types of self-assembly facilitates the generation of binary supramolecular fullerene-containing architectures. Importantly, all functional materials are accessible in a direct fashion. 相似文献
154.
球烯C60与锌酞菁形成电荷迁移络合物的研究 总被引:6,自引:3,他引:6
球烯是一种很有前途的新型非线性光学材料,它具有非平面的共轭离域大Π键体系,具有结合电子的能力,可作为电子受体与电子给体形成电荷迁移络合物(CTC),并能改善有机分子的光学和电学性质[1~4].金属酞青(MPc)也具有共轭大Π键体系,富有π电子,且具有良好的光敏性、化学稳定性及热稳定性.在一定条件下,球烯与金属酞育形成的CTC将大大改善金属酞育的光电性能.因此,研究球烯与金属酞蓄形成的CTC对开拓球烯与金属酞警的应用有重要意义.本文根据C60与锌酞菁(ZnPc)形成的CTC的光谱特征对其组成及相应的平衡常数进行了研究… 相似文献
155.
156.
A facile ultrasound-assisted ion exchange route was developed for the synthesis of CdS/Ag2S heterojunctions by ion exchange between the nanostructured CdS film and [Ag(NH3)2]+ under ultrasonication. The CdS/Ag2S heterojunction film was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis DRS spectroscopy, photoelectrochemical measurements, and the transient photovoltage (TPV) technique. CdSAg2S heterojunctions exhibit a dense morphology, enhanced visible light absorption and stronger photocurrent response than the pure CdS films. Poly(3-hexylthiophene) (P3HT) was then spin coated into the CdS/Ag2S framework. Hybrid solar cells constructed with FTO/CdS/Ag2S/P3HT/Au display relatively higher power conversion efficiency than FTO/CdS/P3HT/Au. 相似文献
157.
Timothy Smith 《Tetrahedron letters》2008,49(3):526-528
Selective DDQ oxidation of 2,5-bis(methylmethoxy)-1,4-di(octyloxy)benzene generates an unsymmetrical subunit suitable for the preparation of substituted tetrameric oligo(phenylenevinylenes) in good to excellent yields. 相似文献
158.
Jie Xue Yuling Huang Dr. Yang Liu Zhongwei Chen Dr. Herman H.-Y. Sung Prof. Dr. Ian D. Williams Prof. Dr. Zonglong Zhu Prof. Dr. Lingling Mao Prof. Dr. Xihan Chen Prof. Dr. Haipeng Lu 《Angewandte Chemie (International ed. in English)》2023,62(29):e202304486
Non-covalent interactions play an essential role in directing the self-assembly of hybrid organic–inorganic crystals. In hybrid halide perovskites, hydrogen bonding has been the paramount non-covalent interaction. Here, we show another non-covalent interaction, namely, the halogen bond interaction, that directs a symmetry-breaking assembly in a new series of two-dimensional (2D) perovskites (ICH2CH2NH3)2(CH3NH3)n−1PbnI3n+1 (n is the layer thickness, n=1–4). Structural analysis shows that the halogen bond strength varies with the layer thickness. For the odd number (n=1, 3) layered perovskites, stronger halogen interaction leads to centrosymmetric structures, whereas for the n=2 layered perovskites, weaker halogen bonds result in non-centrosymmetric structures. Transient reflection spectroscopy shows a suppressed radiative recombination rate (k2≈0) and prolonged spin lifetime for n=2 structure, suggesting an enhanced Rashba band splitting effect. The structural asymmetry is further confirmed with a reversible bulk photovoltaic effect. Our work provides a new design strategy to enable hybrid perovskites with emerging properties and functionalities associated with structural asymmetry. 相似文献
159.
Clean and cheap device, namely dye-sensitized solar cells (DSSCs) were fabricated using a natural dye extracted from Sambucus ebulus. We prepared five sample solutions with various pH in the extraction process to improve power conversion efficiency. The UV–visible absorption investigation of sample solutions and on photoanode show the dyes from J-type aggregation on a photoanode substrate. Redox properties of all sample solutions certify thermodynamically a charge transfer from excited state to conduction band TiO2. The optical properties of various dye solutions were investigated and results showed darkness and bluish tint effect of dye solutions extracted in basic environment rather than those extracted in acidic condition. Moreover, in comparison to the basic condition, the dye solutions extracted in acidic environment were more saturated and colorimetrically less different from that one which extracted in neutral condition. Photophysical and photoelectrochemical performance of natural extraction dyes have been studied in dye-sensitized solar cell devices. The results show the rather high conversion efficiency of 0.57%, 1.15%, 1.02%, 0.35% and 0.15% of each individual dye extraction, respectively. 相似文献
160.
制备了ITO/MEH-PPV/Alq3/LiF/Al光伏(PV)器件. MEH-PPV和Alq3分别为电子受体和给体. 光谱响应曲线主要和Alq3的吸收光谱相匹配. 在功率为0.5 mW·cm2的紫外氙灯照射下电池的短路电流为2.4 μA·cm-2, 开路电压为2.6 V, Fill因子为0.71, 电池的能量转换效率达到0.9%. 在直流电的驱动下, 器件具有电致发光的特性并且发出明亮的桔红色光, 在15 V的直流电压驱动下, 最大亮度达到了1 000 cd·cm-2. 相似文献