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Yu Fu Yanyan Yang Dongxue Chu Zefeng Liu Lili Zhou Xiaoyang Yu Xiaoshu Qu 《Molecules (Basel, Switzerland)》2022,27(13)
Polyoxometalates (POMs) demonstrate potential for application in the development of integrated smart energy devices based on bifunctional electrochromic (EC) optical modulation and electrochemical energy storage. Herein, a nanocomposite thin film composed of a vanadium-substituted Dawson-type POM, i.e., K7[P2W17VO62]·18H2O, and TiO2 nanowires were constructed via the combination of hydrothermal and layer-by-layer self-assembly methods. Through scanning electron microscopy and energy-dispersive spectroscopy characterisations, it was found that the TiO2 nanowire substrate acts as a skeleton to adsorb POM nanoparticles, thereby avoiding the aggregation or stacking of POM particles. The unique three-dimensional core−shell structures of these nanocomposites with high specific surface areas increases the number of active sites during the reaction process and shortens the ion diffusion pathway, thereby improving the electrochemical activities and electrical conductivities. Compared with pure POM thin films, the composite films showed improved EC properties with a significant optical contrast (38.32% at 580 nm), a short response time (1.65 and 1.64 s for colouring and bleaching, respectively), an excellent colouration efficiency (116.5 cm2 C−1), and satisfactory energy-storage properties (volumetric capacitance = 297.1 F cm−3 at 0.2 mA cm−2). Finally, a solid-state electrochromic energy-storage (EES) device was fabricated using the composite film as the cathode. After charging, the constructed device was able to light up a single light-emitting diode for 20 s. These results highlight the promising features of POM-based EES devices and demonstrate their potential for use in a wide range of applications, such as smart windows, military camouflage, sensors, and intelligent systems. 相似文献
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Fatty acids, which are enriched in vegetable oil, have attracted much attention in low-rank coal flotation because of their unique chemical structure. In this study, density functional theory calculations, molecular dynamics simulations, and atomic force microscopy were employed to investigate the adsorption structure and forces between collectors and hydrophilic surfaces. The results show that fatty acids can be easily adsorbed onto surfaces through hydrogen bonds, and can cover the oxygen sites. The existence of hydration film on hydrophilic surfaces prevented nonpolar molecules from being able to adsorb, while polar fatty acids could adsorb and expel water molecules. The adhesion force between the RCOOH-terminated probe and the surface appeared in the retraction process, which differed significantly from that of the RCH3-terminated probe, indicating that polar fatty acids are more suitable as flotation collectors for low-rank coal than nonpolar hydrocarbon oil. The simulation and AFM test revealed the mechanisms of polar fatty acids, and can provide guidance for low-rank coal flotation applications. 相似文献
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纤维素乙醇产业化 总被引:38,自引:0,他引:38
由于能发挥缓解能源紧张、减少环境污染、促进农村发展等重要作用,利用年产量巨大的植物纤维资源,生产可再生性液体替代燃料乙醇的技术受到了巨大的关注,成为工业生物技术的研究热点.酶法生产纤维素乙醇面临多种困难:纤维素原料比重轻,收集运输不便;原料结构复杂,需要深度预处理;纤维素酶系的酶解效率有待提高;半纤维素中的木糖难以发酵转化为乙醇等.经过多年研究,新技术已经取得重大进展,开始接近实用化.紧迫的社会需求正在迫使国内外政府和企业界大量投资,开展纤维素乙醇的中试研究和试生产,力求在短时期内克服上述难点,尽快实现产业化.充分利用植物纤维资源中的多种组分,联合生产乙醇和部分高值产品的生物精练技术,是实现纤维素乙醇产业化的重要突破口和必然途径.玉米芯生物精练生产乙醇和木糖相关产品的技术正在进行产业化.本文综述了纤维素乙醇产业化的研究进展并做了展望. 相似文献
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Synthesis and Rearrangement of P‐Nitroxyl‐Substituted PIII and PV Phosphanes: A Combined Experimental and Theoretical Case Study
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Tobias Heurich Dr. Zheng‐Wang Qu Dr. Senada Nožinović Dr. Gregor Schnakenburg Dr. Hideto Matsuoka Prof. Dr. Stefan Grimme Prof. Dr. Olav Schiemann Prof. Dr. Rainer Streubel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):10102-10110
Low‐temperature generation of P‐nitroxyl phosphane 2 (Ph2POTEMP), which was obtained by the reaction of Ph2PH ( 1 ) with two equivalents of TEMPO, is presented. Upon warming, phosphane 2 decomposed to give P‐nitroxyl phosphane P‐oxide 3 (Ph2P(O)OTEMP) as one of the final products. This facile synthetic protocol also enabled access to P‐sulfide and P‐borane derivatives 7 and 13 , respectively, by using Ph2P(S)H ( 6 ) or Ph2P(BH3)H ( 11 ) and TEMPO. Phosphane sulfide 7 revealed a rearrangement to phosphane oxide 8 (Ph2P(O)STEMP) in CDCl3 at ambient temperature, whereas in THF, thermal decomposition of sulfide 7 yielded salt 10 ([TEMP‐H2][Ph2P(S)O]). As well as EPR and detailed NMR kinetic studies, indepth theoretical studies provided an insight into the reaction pathways and spin‐density distributions of the reactive intermediates. 相似文献
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Xiao-Min Nie Bo-Yang Shao Chen-Hui Qu Ling Zhou 《International Journal of Theoretical Physics》2013,52(9):3011-3019
We generalize usual second-order effective Hamiltonian approximation into third-order. Employing the generalized method, we propose a scheme to generate three-spin interaction using coupled cavity chain. We show that the third order term not only improves two parties interaction but also induces direct three-spin interaction which has not been simulated before. By controlling the frequency of laser field, one can obtain next nearest neighbor interaction on the same order with the nearest neighbor’s or the three-spin interaction on the same order as next nearest neighbor’s. 相似文献
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