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991.
Minghuan Liu Yonggang Liu Guiyang Zhang Lijuan Liu Zhihui Diao Chengliang Yang 《Liquid crystals》2016,43(3):417-426
Control experiments were performed to improve the slope conversion efficiency of the organic distributed feedback laser by varying the dissolution solvents of the laser gain layer, a conjugated polymer poly(2-methoxy-5-(2?-ethyl-hexyloxy)-1,4-phenylene-vinylene) (MEH-PPV) in this work. The distributed feedback configuration of the laser was prepared by holographic photopolymerisation of the polymer/liquid crystal (HPDLC) mixture. Experimental results showed that the tetrahydrofuran (THF) solvent cast laser gain layer had a lower lasing threshold (0.28 μJ/pulse) and a higher slope conversion efficiency (7.8%) than that of the xylene solvent cast laser gain layer (0.5 μJ/pulse, 4.9%). Thin film waveguide characterisation demonstrated that the THF-cast film possessed a smaller waveguide loss (5.3 cm?1) and larger net gain (17.1 cm?1) than the xylene-cast film (8.3 cm?1, 15.7 cm?1). Absorbance and photoluminescence spectra indicated that the THF-cast film showed brighter luminescence at 620 nm and larger absorbance at 532 nm, indicating that the interchain interactions of the MEH-PPV is different, which plays the vital role in improving the optical performance of our organic DFB lasers. 相似文献
992.
Dual‐Doped Molybdenum Trioxide Nanowires: A Bifunctional Anode for Fiber‐Shaped Asymmetric Supercapacitors and Microbial Fuel Cells 下载免费PDF全文
Minghao Yu Xinyu Cheng Yinxiang Zeng Zilong Wang Prof. Yexiang Tong Prof. Xihong Lu Prof. Shihe Yang 《Angewandte Chemie (International ed. in English)》2016,55(23):6762-6766
A novel in situ N and low‐valence‐state Mo dual doping strategy was employed to significantly improve the conductivity, active‐site accessibility, and electrochemical stability of MoO3, drastically boosting its electrochemical properties. Consequently, our optimized N‐MoO3?x nanowires exhibited exceptional performances as a bifunctional anode material for both fiber‐shaped asymmetric supercapacitors (ASCs) and microbial fuel cells (MFCs). The flexible fiber‐shaped ASC and MFC device based on the N‐MoO3?x anode could deliver an unprecedentedly high energy density of 2.29 mWh cm?3 and a remarkable power density of 0.76 μW cm?1, respectively. Such a bifunctional fiber‐shaped N‐MoO3?x electrode opens the way to integrate the electricity generation and storage for self‐powered sources. 相似文献
993.
Margherita Orazietti Dr. Martin Kuss‐Petermann Prof. Dr. Peter Hamm Prof. Dr. Oliver S. Wenger 《Angewandte Chemie (International ed. in English)》2016,55(32):9407-9410
Accumulation and temporary storage of redox equivalents with visible light as an energy input is of pivotal importance for artificial photosynthesis because key reactions, such as CO2 reduction or water oxidation, require the transfer of multiple redox equivalents. We report on the first purely molecular system, in which a long‐lived charge‐separated state (τ≈870 ns) with two electrons accumulated on a suitable acceptor unit can be observed after excitation with visible light. Importantly, no sacrificial reagents were employed. 相似文献
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996.
Tinker LL McDaniel ND Curtin PN Smith CK Ireland MJ Bernhard S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(31):8726-8732
Protons from water are reduced by a catalytic system composed of a heteroleptic iridium(III) photosensitizer [Ir(ppy)2(bpy)]+, platinum catalyst, and sacrificial reductant. The hydrogen quantum yield reaches 0.26 in this study, which proceeds via reductive quenching of the excited photosensitizer by triethanolamine. This simplified approach allows the characterization of degradation products that are otherwise obscured in more complex systems. A novel 16-well setup for parallel kinetic analysis of H2 evolution enables high-throughput screening of reaction conditions and quantization of the decaying reaction rate. DFT calculations rationalize the differences between this and previous studies on tris-diimine ruthenium(II) photosensitizers. 相似文献
997.
Changjiang Hu Dr. Sarah Al Gharib Dr. Yunlong Wang Pingping Gan Qiuhao Li Dr. Sergey A. Denisov Dr. Sophie Le Caer Dr. Jacqueline Belloni Prof. Jun Ma Prof. Mehran Mostafavi 《Chemphyschem》2021,22(18):1900-1906
The present study proposes a new approach for direct CO2 conversion using primary radicals from water irradiation. In order to ensure reduction of CO2 into CO2−. by all the primary radiation-induced water radicals, we use formate ions to scavenge simultaneously the parent oxidizing radicals H. and OH. producing the same transient CO2−. radicals. Conditions are optimized to obtain the highest conversion yield of CO2. The goal is achieved under mild conditions of room temperature, neutral pH and 1 atm of CO2 pressure. All the available radicals are exploited for selectively converting CO2 into oxalate that is accompanied by H2 evolution. The mechanism presented accounts for the results and also sheds light on the data in the literature. The radiolytic approach is a mild and scalable route of direct CO2 capture at the source in industry and the products, oxalate salt and H2, can be easily separated. 相似文献
998.
Zhongqiang Wang Lu Qi Zhiqiang Zheng Prof. Yurui Xue Prof. Yuliang Li 《化学:亚洲杂志》2021,16(21):3259-3271
Two-dimensional (2D) graphdiyne (GDY), a rapidly rising star on the horizon of carbon materials, is a new carbon allotrope featuring sp- and sp2-cohybridized carbon atoms and 2D one-atom-thick network. Since the first successful synthesis of GDY by Professor Li's group in 2010, GDY has attached great interests from both scientific and industrial viewpoints based on its unique structure and physicochemical properties, which provides a fertile ground for applications in various fields including electrocatalysis, energy conversion, energy storage and optoelectronic devices. In this work, various potential properties of the GDY-based electrocatalysts and their recent advances in energy conversion are reviewed, including atomic catalysts, heterogeneous catalysts, and metal-free catalysts. The critical role of GDY in improving catalytic activity and stability is analyzed. The perspectives of the challenges and opportunities faced by GDY-based materials for energy conversion are also outlined. 相似文献
999.
Kodchakon Kun-asa Prof. Prasert Reubroycharoen Dr. Kiyoyuki Yamazaki Dr. Naoki Mimura Dr. Osamu Sato Dr. Aritomo Yamaguchi 《ChemistryOpen》2021,10(3):308-315
Although chitin, an N-acetyl-D-glucosamine polysaccharide, can be converted to valuable products by means of homogeneous catalysis, most of the chitin generated by food processing is treated as industrial waste. Thus, a method for converting this abundant source of biomass to useful chemicals, such as lactic acid, would be beneficial. In this study, we determined the catalytic activities of various metal oxides for chitin conversion at 533 K and found that MgO showed the highest activity for lactic acid production. X-ray diffraction analysis and thermogravimetry-differential thermal analysis showed that the MgO was transformed to Mg(OH)2 during chitin conversion. The highest yield of lactic acid (10.8 %) was obtained when the reaction was carried out for 6 h with 0.5 g of the MgO catalyst. The catalyst could be recovered as a solid residue after the reaction and reused twice with no decrease in the lactic acid yield. 相似文献
1000.