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311.
Xuejiao Tang Haitao Liao Tao Zheng Pan Yin Prof. Jing Cao Assoc. Prof. Xiaoying Zeng Dr. Chao Weng Prof. Ping Shen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(58):14508-14519
Two dithienocyclopentafluorene-based small-molecule acceptors (SMAs) were developed that feature methylene-functionalized conjugated side chains, to study the effect of arylmethylene substitution and its number on structure, optoelectronic properties and device performance. Results showed that two SMAs have better absorption properties and planarity, lower bandgaps and higher LUMOs compared with the control SMA without conjugated side chains. The synthesized SMAs were tested in polymer solar cells for examples of their applicability. This work argues that the introduction of methylene-functionalized conjugated side chains has great potential in tuning molecular structure, optoelectronic properties, device physics and photovoltaic performance of SMAs. 相似文献
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Kangli Min Fengzhen Huang Xiaomei Lu Yi Kan Junting Zhang Song Peng Yaoyang Liu Jie Su Chao Zhang Zijian Liu Jinsong Zhu 《Solid State Communications》2012,152(4):304-306
KNb0.95Co0.05O3 (KN–Co) ceramic was prepared via a solid-state reaction method, and the effect of cobalt dopant on the structural, electric, and magnetic properties was studied. The KN–Co ceramic with polycrystalline perovskite structure exhibited ferromagnetic and ferroelectric properties simultaneously at room temperature, and the coupling of them was confirmed by a large magnetocapacitance effect (about 13%) near the Curie temperature. The possible causes for the magnetism and magnetoelectric properties are discussed. 相似文献
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Yibo Zhang Prof. Yuying Zheng Prof. Hongbo Geng Dr. Yang Yang Dr. Minghui Ye Dr. Yufei Zhang Prof. Cheng Chao Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):9031-9037
Metal phosphates have been widely explored in lithium ion batteries and sodium ion batteries owing to high theoretical capacities, mild toxicity and low cost. However, their potassium ion battery applications are less reported due to the limited conductivity and the slow diffusion kinetics. Considering these drawbacks, novel structured M2P2O7/C (M=Fe, Co, Ni) nanoflake composites are prepared through an organic-phosphors precursor-assisted solvothermal method and a subsequent high temperature annealing process. The designed Co2P2O7/C composite exhibits the highest rate capacity with 502 mAh g−1 at 0.1 A g−1 and good cyclability for 900 cycles at 1 A g−1 and 2 A g−1 when compared with Ni and Fe based composites. The superior electrochemical performance can be attributed to their unique nanoparticle-assembled nanoflake structure, which can afford enough active sites for K+ intercalation. In addition, the robust pyrophosphate crystal structure and the in situ formed carbon composition also have positive effects on enhancing the long-term cycling performance and the electrode's conductivity. Finally, this organic-phosphors precursor induced simple approach can be applied for easy fabrication of other pyrophosphate/carbon hybrids as advanced electrodes. 相似文献
316.
Xing Chen Wenguang Zhao Feng Wang Jie Xu .Dalian National Laboratory for Clean Energy State 《天然气化学杂志》2012,(5):481-487
Preparation of dispersed transition metal oxides catalyst with low oxidation state still remains a challenging task in heterogeneous catalysis.In this study,vanadium oxides supported on zeolite SBA-15 have been prepared under hydrothermal condition using V 2 O 5 and oxalic acid as sources of vanadium and reductant,respectively.The structures of samples,especially the oxidation state of vanadium,and the surface distribution of vanadium oxide species,have been thoroughly characterized using various techniques,including N 2-physisorption,X-ray diffraction(XRD),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),UV-visible spectra(UV-Vis) and UV-visible-near infrared spectra(UV-Vis-NIR).It is found that the majority of supported vanadium was in the form of vanadium(IV) oxide species with the low valence of vanadium.By adjusting hydrothermal treatment time,the surface distribution of vanadium(IV) oxide species can be tuned from vanadium(IV) oxide cluster to crystallites.These materials have been tested in the hydroxylation of benzene to phenol in liquid-phase with molecular oxygen in the absence of reductant.The catalyst exhibits high selectivity for phenol(61%) at benzene conversion of 4.6%,which is a relatively good result in comparison with other studies employing molecular oxygen as the oxidant. 相似文献
317.
Hang Ma Yang He Ruo-Feng Huang Xiao-Hui Zhang Jing Pan Jia-Qiang Li Chao He Xue-Ge Ling Xuan-Lun Wang Yan Xiong 《中国化学快报》2014,25(10):1327-1330
Under neat conditions,an efficient method for synthesis of imidoesters has been developed using cyanatobenzenes and dicarbonyl compounds.Nucleophilic addition spontaneously occurred between the two kinds of materials at room temperature with yields of up to 90%.A mechanism directed towards to the imidoester formation has been proposed. 相似文献
318.
Straight-chain aliphatic terr-amine N-oxides were found to be useful oxidizing agent for epoxidation of tri- and tetra-substituted perfluoroalkenes under mild conditions in high yields.The process for epoxidation by employing tri-n-butylamine N-oxide gave the best result in the reagent survey. 相似文献
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