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1.
Organic solar cells (OSCs) harvesting indoor light are highly promising for emerging technologies, such as internet of things. Herein, the photovoltaic performance of PTB7-Th:PC71BM solar cells constructed using “optimized (with 1,8-diiodooctane (DIO))” and “non-optimized (without DIO)” processing conditions are compared for indoor and outdoor applications. We find that in comparison to the “optimized” solar cell, the “non-optimized” solar cell is less efficient under simulated solar light illumination (100 mW cm−2, spectral range 350–1100 nm), owing to significant bimolecular charge carrier recombination losses. However, under simulated indoor illumination (3.28 mW cm−2, spectral range 400–700 nm), bimolecular recombination losses are effective suppressed, thus the power conversion efficiency of the solar cell without DIO was increased to 14.7 %, higher than that of the solar cell with DIO (14.2 %). These results suggest that the common strategy used to optimize the OSCs could be undesired for indoor OSCs. We demonstrate that the efforts for realizing the desired “morphology” of the active layer for the outdoor OSCs may be unnecessary for indoor OSCs, allowing us to realize high-efficiency indoor OSCs using a non-halogenated solvent. 相似文献
2.
Dr. Nataliia S. Kariaka Dr. Victor A. Trush Dr. Viktoriya V. Dyakonenko Dr. Svitlana V. Shishkina Dr. Sergii S. Smola Dr. Nataliia V. Rusakova Dr. Tetiana Y. Sliva Dr. Paula Gawryszewska Dr. Albano N. Carneiro Neto Prof. Dr. Oscar L. Malta Prof. Dr. Vladimir M. Amirkhanov 《Chemphyschem》2022,23(14):e202200129
New lanthanide dimethyl-N-benzoylamidophosphate (HL) based tetrakis-complexes NEt4[LnL4] (Ln3+=La, Nd, Sm, Eu, Gd, Tb, Dy) are reported. The complexes are characterized by means of NMR, IR, absorption, and luminescent spectroscopy as well as by elemental, X-Ray, and thermal gravimetric analyses. The phenyl groups of the four ligands of the complex anion are directed towards one side, while the methoxy groups are directed in the opposite side, which makes the complexes under consideration structurally similar to calixarenes. The effect of changing the alkali metal counterion to the organic cation NEt4+ on the structure and properties of the tetrakis-complex [LnL4]- is analyzed. The complexes exhibit bright characteristic for respective lanthanides luminescence. Rather high intensity of the band of 5D0→7F4 transition, observed in the luminescence spectrum of NEt4[EuL4], is discussed based on theoretical calculations. 相似文献
3.
Circularly polarized luminescence (CPL) has attracted attention as a next-generation light signal because of its carrying more information compared with normal and linearly polarized lights as well as its potential wide application in information fields. Recently, much attention has been paid to small organic molecules-based CPL emitters because of easy synthesis, fine structural modification at molecular level, and tunable wide range emission wavelength. This review highlights the development of small organic molecules-based CPL emitters in the past 5 years (2017–2021). The progress suggests that small organic molecules-based CPL emitters provide a simple and efficient way to generate CPL. 相似文献
4.
学习体验是学生对学习内容、过程、方法、意义的自我感受和评估,对学生学习志趣、学习素养提升有积极正向作用。以钠及其化合物复习为例,将各类别物质间转化关系的构建、物质制备原理和条件的优选作为学习体验对象,依据学习体验的内在发展历程设计学习任务及活动,引导学生亲身体验学科认知方式、学科思维方法、学科应用价值,评价体验结果,激励学生自主学习发生。 相似文献
5.
采用固相反应法合成了一种Zr Cu Si As型准二维层状锰基化合物Th Mn Sb N.基于X射线粉末衍射的结构精修显示,该化合物属于P4/nmm空间群.其晶胞参数为a=4.1731?, c=9.5160?.电输运测量显示,该化合物电阻率随温度下降缓慢上升,且在16 K附近出现电阻率异常.与此同时,该材料的磁化率在同一温度附近出现异常,显示出类似磁性相变的行为.进一步的比热测量中没有观察到磁相变导致的比热异常.另外,低温下的比热分析显示,该材料的电子比热系数为γ=19.7 m J·mol–1·K–2,远高于其他同类锰基化合物.该结果与电输运测量中观察到的低电阻率行为相符,暗示Th Mn Sb N中费米面附近存在可观的电子态密度.基于对一系列Zr Cu Si As型化合物晶体结构细节的比较,分析了含有萤石型Th2N2层的系列化合物中导电层所受化学压力的不同作用形式. 相似文献
6.
二维液相色谱(2D-LC)因具有较高的峰容量,在复杂样品的分离分析中获得了广泛的关注。然而,制备型2D-LC以纯化高纯单体为目标,在方法开发和设备构成等方面与分析型2D-LC有较大的不同,目前尚未得到充分的开发,在大规模的制备纯化中应用较少。本文以一套制备液相色谱模块为分离系统,以稀释泵、切换阀和捕集柱阵列为接口,构建了新型的制备型2D-LC系统,旨在规模化纯化多个活性成分。以烟叶中可以用作医药原料的烟碱、绿原酸、芦丁和茄尼醇等组分为目标物,考察了不同类型填料对样品的捕集效率、过载条件下的色谱保留行为等,优化了制备色谱条件。进而利用在线2D-LC系统实现了烟叶提取物的纯化,通过一次运行获得了4个高纯化合物。该系统具有中压色谱纯化成本低、系统在线运行自动化程度高、稳定性好及容易放大等优点。烟叶中活性化学成分的回收利用对促进烟草行业的发展及带动地方农业经济开发具有重大的意义。 相似文献
7.
Dye-sensitized solar cells (DSSCs) are the most promising alternatives to traditional fossil energy because of their advantages of low production cost, facile structure, relatively low environmental impact, relatively high photoelectronic absorption efficiency, and overall high efficiency. In addition, several studies on sensitizers as vital components have been conducted over the last three decades. Compared to metal dyes, metal-free organic dyes have been considered as promising candidates because of their simple fabrication, multiple structures, high molar absorption coefficients, easily tunable properties, and environmental friendliness. In this study, we systematically investigated the optoelectronic properties of six metal-free organic donor-acceptor dyes (RD1–6) derived from the known dye R6 by using the density functional theory (DFT) and time-dependent DFT methods. Cell performance parameters were discussed, including the geometrical and electronic structures, absorption spectrum, adsorption energy, light harvesting efficiency (LHE) curve, predictive short circuit current density (JscPred.), predictive open circuit voltage (VocPred.), and theoretical power conversion efficiency (PCE). Results revealed that all the designed dyes exhibited high theoretical PCE. In particular, dyes RD1, 2, and 4–6 showed greater conjugations, and dyes RD1–3 had smaller energy gaps than those of the reference dye. In addition, dyes RD1–3, 5, and 6 exhibited better light harvesting capacities that covered the entire visible region and extended to the near-infrared region with obviously red-shift maximum absorption wavelengths (λmax), wider LHE curves, and higher JscPred. as compared to the reference dye. It was critical that dyes RD1 and 2 not only have greater conjugations and narrow band gaps but also good light harvesting capacities with more than 56-nm red-shift maximum absorption wavelengths and broadened LHE curves than those of the reference dye. Notably, mainly because of an average increment of 12.0% of JscPred., a remarkable increment of the theoretical power conversion efficiency was observed from 12.6% for dye R6 to 14.1% for dyes RD1 and 2. Thus, dyes RD1 and 2 exhibited superior cell performances and could be promising sensitizer candidates for highly efficient DSSCs. These results could be used to guide effective synthetic efforts in the discovery of efficient metal-free organic dye sensitizers in DSSCs. 相似文献
8.
铈基催化剂由于其特殊的氧化还原性能在催化反应中得到了广泛应用,在非均相催化反应中其表面性质尤为重要.二氧化铈晶格中的氧缺陷对表面催化反应起着非常重要的作用,而二氧化铈可以有效调节催化剂表面酸碱性,修饰催化活性中心的结构,提高催化剂的储放氧能力,增强其结构稳定性和提高活性组分的分散度等.我们分别从二氧化铈催化剂的制备方法、催化剂活性位点和种类、氧缺陷性质及与催化性能之间的构效关系、纯二氧化铈及作为载体的二氧化铈基催化材料催化燃烧挥发性有机物等方面综述了二氧化铈基催化剂的最新研究进展.最后提出了二氧化铈基催化剂在挥发性有机物治理应用中的建议与展望. 相似文献
9.
10.
传统的塑料闪烁体由于其低有效原子序数和密度,不适用于能谱探测领域。有机重金属化合物掺杂塑料闪烁体的制备为塑料闪烁体实现能谱探测提供了一种有效途径。而有机锡化合物掺杂塑料闪烁体具有高光峰灵敏度,并保留了塑料闪烁体的快衰减特性。本文通过自由基聚合的方法成功制备了不同浓度2-(三丁基锡烷基)呋喃掺杂的聚乙烯基甲苯(PVT)基塑料闪烁体,并对其光学和闪烁性能进行了测试和比较。其中掺杂20%2-(三丁基锡烷基)呋喃的PVT基塑料闪烁体的透光率可达90%,X射线激发发射光谱主峰位于425 nm处,光产额为6700 ph/MeV,能量分辨率为15.8%@662 keV,衰减时间约为4.3 ns。我们也制备了1英寸直径、掺杂20%2-(三丁基锡烷基)呋喃的塑料闪烁体,具有6300 ph/MeV的光产额和15.8%@662 keV的能量分辨率。 相似文献