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11.
Regulation of Charge Delocalization in a Heteronuclear Fe2Ru System by a Stepwise Photochromic Process 下载免费PDF全文
Guang‐Tao Xu Dr. Bin Li Dr. Jin‐Yun Wang Dr. Dao‐Bin Zhang Prof. Zhong‐Ning Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3318-3326
Heteronuclear complexes FeCp2?DTE?C?C?Ru(dppe)2Cl ( 1 o ; dppe=1,2‐bis(diphenylphosphino)ethane, Cp=cyclopentadienyl, DTE=dithienylethene) and FeCp2?DTE?C?C?Ru(dppe)2?C?C?DTE?FeCp2 ( 2 oo ), with redox‐active ferrocenyl and ruthenium centers separated by a photochromic DTE moiety, were prepared to achieve photoswitchable charge delocalization and Fe???Ru electronic communication. Upon UV‐light irradiation of 2 oo , the Fe???Ru heterometallic electronic interaction is increasingly facilitated with stepwise photocyclization, 2 oo → 2 co → 2 cc ; this is ascribed to the gradual increase in π‐conjugated systems. The near‐infrared absorptions in mixed‐valence species [ 2 oo ]+/[ 2 co ]+/[ 2 cc ]+ are gradually intensified following the conversion of [ 2 oo ]+→[ 2 co ]+→[ 2 cc ]+, which demonstrates that the extent of charge delocalization shows progressive enhancement with stepwise photocyclization. As revealed by electrochemical, spectroscopic, and theoretical studies, complex 2 exhibits nine switchable states through stepwise photochromic and reversible redox processes. 相似文献
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Molecular triplets have attracted great interest across multidisciplinary fields of the research ranging from thermally activated delayed fluorescence[1],triplet-triplet annihilation(TTA)upconversion[2],to photodynamic therapy relying on TTA between triplet photosensitizers and surrounding triplet oxygen to generate singlet oxygen species[3]. 相似文献
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Yi Liu Jiaqi Wang Shiguo Han Dr. Xitao Liu Maofan Li Zhiyun Xu Wuqian Guo Prof. Maochun Hong Prof. Junhua Luo Prof. Zhihua Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3494-3498
3D perovskite CsPbBr3 has recently taken a blooming position for optoelectronic applications. However, due to the lack of natural anisotropy of optical attributes, it is a great challenge to fulfil polarization-sensitive photodetection. Here, for the first time, we exploited dimensionality reduction of CsPbBr3 to tailor a 2D-multilayered hybrid perovskite, (TRA)2CsPb2Br7 ( 1 , in which TRA is (carboxy)cyclohexylmethylammonium), serving as a potential polarized-light detecting candidate. Its unique quantum-confined 2D structure results in intrinsic anisotropy of electrical conductivity, optical absorbance, and polarization-dependent responses. Particularly, it exhibits remarkable dichroism with the photocurrent ratio (Ipc/Ipa) of ≈2.1, being much higher than that of the isotropic CsPbBr3 crystal and reported CH3NH3PbI3 nanowire (≈1.3), which reveals its great potentials for polarization-sensitive photodetection. Further, crystal-based detectors of 1 show fascinating responses to the polarized light, including high detectivity (>1010 Jones), fast responding time (≈300 μs), and sizeable on/off current ratios (>104). To our best knowledge, this is the first study on 2D Cs-based hybrid perovskite exhibiting strong polarization-sensitivity. The work highlights an effective pathway to explore new polarization sensitive candidates for hybrid perovskites and promotes their future electronic applications. 相似文献
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Dr. Huixin Fan Prof. Chensheng Lin Kaichuang Chen Dr. Guang Peng Dr. Bingxuan Li Prof. Ge Zhang Prof. Xifa Long Prof. Ning Ye 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(13):5306-5310
An ammonium-containing metal iodate fluoride compound, (NH4)Bi2(IO3)2F5, featuring a two-dimensional double-layered framework constructed by [BiO2F5]6− and [BiO4F4]9− polyhedra, as well as [IO3]− groups, was successfully synthesized. The well-ordered alignment of these SHG-active units leads to an extraordinary strong SHG response of 9.2 times that of KDP. Moreover, this compound possesses a large birefringence (Δn=0.0690 at 589.3 nm), a wide energy band gap (Eg=3.88 eV), and a high laser damage threshold (LDT; 40.2×AgGaS2). In particular, thermochromic behavior was observed for the first time in this type of compound. Such multifunctional crystals will expand the application of nonlinear optical materials. 相似文献
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《结构化学》2020,39(6):1063-1069
In this text, we present researches on the synthesis of polyoxo-titanium clusters(PTCs) by the use of gadolinium pivalate precursor. During the synthesis process, we discover that solvents play an important role. When acetonitrile was used as solvent, Ti_8Gd(μ_2-O)(μ_3-O)_5(Sal)_5(OPiv)_2(μ_2-O~iPr)_3(μ-O~iPr)_8(PTC-82)(H_2Sal = salicylic acid, HOPiv = pivalic acid) was obtained. When N,N-dimethylformamide(DMF) was used as solvent under the same reaction conditions, Ti_4Gd_2(μ_3-O)_2(Sal)_4(OPiv)_4(μ_2-O~iPr)_2(μ-O~iPr)_4(DMF)2(PTC-83) was synthesized. The solid-state UV absorption spectra revealed that the dopant of lanthanide and the incorporation of salicylic acid ligands have successfully narrowed the bandgap of PTCs. In addition, they exhibited rapid and reproducible photo-responses. 相似文献
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Nonlinear Dynamics - In this study, we propose the fluctuating-mass generalized Langevin equation (GLE) with a tempered Mittag-Leffler (M-L) noise, and investigate the generalized stochastic... 相似文献
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Tingke Rao Prof. Maria Luisa Saladino Prof. Yuanxing Fang Prof. Xinchen Wang Dr. Cristina Giordano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(72):16676-16682
A versatile synthetic strategy for the preparation of multimetallic oxynitrides has been designed and here exemplarily discussed considering the preparation of nanoscaled zinc–gallium oxynitrides and zinc–gallium–indium oxynitrides, two important photocatalysts of new generation, which proved to be active in key energy related processes from pollutant decomposition to overall water splitting. The synthesis presented here allows the preparation of small nanoparticles (less than 20 nm in average diameter), well-defined in size and shape, yet highly crystalline and with the highest surface area reported so far (up to 80 m2 g−1). X-ray diffraction studies show that the final material is not a mixture of single oxides but a distinctive compound. The photocatalytic properties of the oxynitrides have been tested towards the decomposition of an organic dye (as a model reaction for the decomposition of air pollutants), showing better photocatalytic performances than the corresponding pure phases (reaction constant 0.22 h−1), whereas almost no reaction was observed in absence of catalyst or in the dark. The photocatalysts have been also tested for H2 evolution (semi-reaction of the water splitting process) with results comparable to the best literature values but leaving room for further improvement. 相似文献