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51.
Qianxi Dang Lanzhen Hu Jiaqiang Wang Qunhua Zhang Mengmeng Han Simeng Luo Yanbin Gong Can Wang Prof. Qianqian Li Prof. Zhen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):7031-7037
Organic luminescence with different forms continues to be one of the most active research fields in science and technology. Herein, an ultra-simple organic molecule (TPA-B), which exhibits both mechanoluminescence (ML) and photo-induced room-temperature phosphorescence (RTP) in the crystalline state, provides an opportunity to reveal the internal mechanism of ML and the dynamic process of photo-induced RTP in the same molecule. Through the detailed investigation of photophysical properties together with crystal structures, the key role of molecular packing and intermolecular interactions was highlighted in the luminescence response by mechanical and light stimulus, affording efficient strategies to design potential smart functional materials with multiple luminescence properties. 相似文献
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Mengmeng Zhang Dr. Jiajun Wang Hui Xue Dr. Jinfeng Zhang Prof. Dr. Shengjie Peng Dr. Xiaopeng Han Prof. Dr. Yida Deng Prof. Dr. Wenbin Hu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18621-18625
Cu2O is a typical photoelectrocatalyst for sustainable hydrogen production, while the fast charge recombination hinders its further development. Herein, Ni2+ cations have been doped into a Cu2O lattice (named as Ni-Cu2O) by a simple hydrothermal method and act as electron traps. Theoretical results predict that the Ni dopants produce an acceptor impurity level and lower the energy barrier of hydrogen evolution. Photoelectrochemical (PEC) measurements demonstrate that Ni-Cu2O exhibits a photocurrent density of 0.83 mA cm−2, which is 1.34 times higher than that of Cu2O. And the photostability has been enhanced by 7.81 times. Moreover, characterizations confirm the enhanced light-harvesting, facilitated charge separation and transfer, prolonged charge lifetime, and increased carrier concentration of Ni-Cu2O. This work provides deep insight into how acceptor-doping modifies the electronic structure and optimizes the PEC process. 相似文献
54.
Han Huiyun Li Xingliang Han Mengmeng Liu Jingmin Yan Dan Yang Zhenjun Shang Ce Feng Yali Zhang Shumin 《Optical Review》2018,25(2):237-243
Optical Review - We have numerically investigated the required minimum cavity dispersion (RMCD) for obtaining stable pulses in net normal dispersion, graphene mode-locked, Yb-doped fiber lasers... 相似文献
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Spatially Separated CdS Shells Exposed with Reduction Surfaces for Enhancing Photocatalytic Hydrogen Evolution
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Mingyang Xing Bocheng Qiu Mengmeng Du Qiaohong Zhu Lingzhi Wang Jinlong Zhang 《Advanced functional materials》2017,27(35)
To the photocatalytic H2 evolution, the exposure of a reduction surface over a catalyst plays an important role for the reduction of hydrogen protons. Here, this study demonstrates the design of a noble‐metal‐free spatially separated photocatalytic system exposed with reduction surfaces (MnOx @CdS/CoP) for highly solar‐light‐driven H2 evolution activity. CoP and MnOx nanoparticles are employed as the electron and hole collectors, which are selectively anchored on the outer and inner surface of CdS shells, respectively. Under solar light irradiation, the photogenerated holes and electrons can directionally move to the MnOx and CoP, respectively, leading to the exposure of a reduction surface. As a result, the H2 evolution increases from 32.0 to 238.4 µmol h?1, which is even higher than the activity of platinum‐loaded photocatalyst (MnOx @CdS/Pt). Compared to the pure CdS with serious photocorrosion, the MnOx @CdS/CoP maintains a changeless activity for the H2 evolution and rhodamine B degradation, even after four cycles. The research provides a new strategy for the preparation of spatially separated photocatalysts with a selective reduction surface. 相似文献
57.
Dr. Huanhuan Shi Prof. Mengmeng Li Shuai Fu Dr. Christof Neumann Dr. Xiaodong Li Dr. Wenhui Niu Yunji Lee Prof. Mischa Bonn Dr. Hai I. Wang Prof. Andrey Turchanin Dr. Ali Shaygan Nia Dr. Sheng Yang Prof. Xinliang Feng 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303929
Two-dimensional van der Waals heterostructures (2D vdWHs) have recently gained widespread attention because of their abundant and exotic properties, which open up many new possibilities for next-generation nanoelectronics. However, practical applications remain challenging due to the lack of high-throughput techniques for fabricating high-quality vdWHs. Here, we demonstrate a general electrochemical strategy to prepare solution-processable high-quality vdWHs, in which electrostatic forces drive the stacking of electrochemically exfoliated individual assemblies with intact structures and clean interfaces into vdWHs with strong interlayer interactions. Thanks to the excellent combination of strong light absorption, interfacial charge transfer, and decent charge transport properties in individual layers, thin-film photodetectors based on graphene/In2Se3 vdWHs exhibit great promise for near-infrared (NIR) photodetection, owing to a high responsivity (267 mA W−1), fast rise (72 ms) and decay (426 ms) times under NIR illumination. This approach enables various hybrid systems, including graphene/In2Se3, graphene/MoS2 and graphene/MoSe2 vdWHs, providing a broad avenue for exploring emerging electronic, photonic, and exotic quantum phenomena. 相似文献
58.
An easy method to prepare solid phase microextraction fibers by introducing an inorganic binder was demonstrated in this study, where MoS2 was selected as the extraction phase material because of its graphite-like layered structure with large specific adsorption area and good stability, and was then adhered to a stainless steel wire by acid aluminum phosphate binder with the spraying method. The as-prepared solid phase microextraction fiber coupled with gas chromatography was then used to extract some polycyclic aromatic hydrocarbons target analytes including the low-volatile benzo(a)pyrene etc. from a standard sample. Comparing with the MoS2-epoxy resin and commercial polyacrylate fibers, the MoS2-acid aluminum phosphate fiber has a higher thermal stability because of highly thermal stable acid aluminum phosphate, which is durable for a long service life at a high temperature (320 °C), and has the advantage in the extraction of low-volatility analytes. After the optimization of adsorption and desorption factors (ionic strength, adsorption time and temperature, and desorption temperature), method detection limits of <0.1 μg L−1 were achieved, and the calibration curves were all linear (R2 ≥ 0.9981) within the range of 0.1–100 μg L−1. The satisfying repeatability was also achieved, the RSD values of single-fiber were 3.49–5.81%, and the ones of fiber-to-fiber were 5.32–7.22%. As a result, the present fiber with good thermal stability can work at high temperature for a long service life, which is useful for the detection of low-volatility target analytes in practical applications. 相似文献
59.
研究一类具有分数阶线性微分算子的非线性微分方程积分边值问题解的存在性与唯一性.利用Schauder不动点定理及压缩映射原理,建立并证明了边值问题解的存在性定理和唯一性定理,并给出两个例子以说明所得结论. 相似文献
60.
Jingjing Yu Daxiang Liu Zhenyu Ding Yanan Yuan Jiayuan Zhou Fangfang Pei Haolin Pan Tianping Ma Feng Jin Lingfei Wang Wenguang Zhu Shouguo Wang Yizheng Wu Xue Liu Dazhi Hou Yang Gao Ziqiang Qiu Mengmeng Yang Qian Li 《Advanced functional materials》2024,34(2):2307259
The advent of van der Waals (vdW) ferromagnetic (FM) and antiferromagnetic (AFM) materials offers unprecedented opportunities for spintronics and magneto-optic devices. Combining magnetic Kerr microscopy and density functional theory calculations, the AFM-FM transition is investigated and a surprising abnormal magneto-optic anisotropy in vdW CrSBr associated with different magnetic phases (FM, AFM, or paramagnetic state) is discovered. This unique magneto-optic property leads to different anisotropic optical reflectivity from different magnetic states, permitting direct imaging of the AFM Néel vector orientation and the dynamic process of the AFM-FM transition within a magnetic field. Using Kerr microscopy, not only the domain nucleation and propagation process is imaged but also the intermediate spin-flop state in the AFM-FM transition is identified. The unique magneto-optic property and clear identification of the dynamics process of the AFM-FM phase transition in CrSBr demonstrate the promise of vdW magnetic materials for future spintronic technology. 相似文献