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81.
Wei Zong Haiqi Gao Yue Ouyang Kaibin Chu Hele Guo Leiqian Zhang Wei Zhang Ruwei Chen Yuhang Dai Fei Guo Jiexin Zhu Zhenfang Zhang Chumei Ye Dr. Yue-E. Miao Prof. Johan Hofkens Dr. Feili Lai Prof. Tianxi Liu 《Angewandte Chemie (International ed. in English)》2023,62(27):e202218122
Competition from hydrogen/oxygen evolution reactions and low solubility of N2 in aqueous systems limited the selectivity and activity on nitrogen fixation reaction. Herein, we design an aerobic-hydrophobic Janus structure by introducing fluorinated modification on porous carbon nanofibers embedded with partially carbonized iron heterojunctions (Fe3C/Fe@PCNF-F). The simulations prove that the Janus structure can keep the internal Fe3C/Fe@PCNF-F away from water infiltration and endow a N2 molecular-concentrating effect, suppressing the competing reactions and overcoming the mass-transfer limitations to build a robust “quasi-solid–gas” state micro-domain around the catalyst surface. In this proof-of-concept system, the Fe3C/Fe@PCNF-F exhibits excellent electrocatalytic performance for nitrogen fixation (NH3 yield rate up to 29.2 μg h−1 mg−1cat. and Faraday efficiency (FE) up to 27.8 % in nitrogen reduction reaction; NO3− yield rate up to 15.7 μg h−1 mg−1cat. and FE up to 3.4 % in nitrogen oxidation reaction). 相似文献
82.
Xinliang Cai Yexuan Pu Prof. Chenglong Li Dr. Zhiheng Wang Prof. Yue Wang 《Angewandte Chemie (International ed. in English)》2023,62(27):e202304104
Multi-resonance thermally activated delayed fluorescence (MR-TADF) materials are considered a class of organic materials with exceptional electronic and optical properties, which make them promising for the applications in organic light-emitting diodes (OLEDs). In this study, we improved, synthesized, and characterized a multiple-resonance type emitter based on the assembly of MR-building blocks (MR-BBs). By optimizing the geometric arrangement of MR-BBs, we were able to generate narrowband emission in the longer wavelength region and shorten the delayed excited-state lifetime, resulting in improved emission efficiency compared to the parent molecule. Our proof-of-concept molecule, m-DBCz, exhibited narrowband yellowish-green TADF emission with a full width at half-maximum of 32 nm and a small singlet-triplet energy gap of 0.04 eV. The OLED developed using m-DBCz as the emitter demonstrated electroluminescence at 548 nm and achieved a high external quantum efficiency (EQE) of 34.9 %. Further optimization of the device resulted in a high external quantum efficiency of 36.3 % and extremely low efficiency roll-off, with EQE values of 30.1 % and 27.7 % obtained even at high luminance levels of 50 000 and 100 000 cd m−2. These results demonstrate the full potential of MR-TADF materials for applications on ultrahigh-luminance OLEDs. 相似文献
83.
Dr. Yang Wei Dr. Yue Pan Dr. Enlong Zhou Dr. Ze Yuan Dr. Hao Song Dr. Yilin Wang Dr. Jie Zhou Jiahui Rui Mengjiao Xu Prof. Lixin Ning Dr. Zhanning Liu Dr. Hongyu Wang Prof. Xiaoji Xie Prof. Xiaobin Tang Prof. Haiquan Su Xianran Xing Prof. Ling Huang 《Angewandte Chemie (International ed. in English)》2023,62(27):e202303482
Although large amount of effort has been invested in combating thermal quenching that severely degrades the performance of luminescent materials particularly at high temperatures, not much affirmative progress has been realized. Herein, we demonstrate that the Frenkel defect formed via controlled annealing of Sc2(WO4)3:Ln (Ln=Yb, Er, Eu, Tb, Sm), can work as energy reservoir and back-transfer the stored excitation energy to Ln3+ upon heating. Therefore, except routine anti-thermal quenching, thermally enhanced 415-fold downshifting and 405-fold upconversion luminescence are even obtained in Sc2(WO4)3:Yb/Er, which has set a record of both the Yb3+-Er3+ energy transfer efficiency (>85 %) and the working temperature at 500 and 1073 K, respectively. Moreover, this design strategy is extendable to other hosts possessing Frenkel defect, and modulation of which directly determines whether enhanced or decreased luminescence can be obtained. This discovery has paved new avenues to reliable generation of high-temperature luminescence. 相似文献
84.
Jiahui Zeng Yu Fu Yue Wu Shanshan Wang Wenxiang Zhang Prof. Heping Ma 《Angewandte Chemie (International ed. in English)》2023,62(42):e202310235
Xe is an ideal anesthetic gas, but it has not been widely used in practice due to its high cost and low output. Closed-circuit Xe recovery and recycling is an economically viable method to ensure adequate supply in medical use. Herein, we design an innovative way to recover Xe by using a stable fluorinated metal-organic framework (MOF) NbOFFIVE-1-Ni to eliminate CO2 from moist exhaled anesthetic gases. Unlike other Xe recovery MOFs with low Xe/CO2 selectivity (less than 10), NbOFFIVE-1-Ni could achieve absolute molecular sieve separation of CO2/Xe with excellent CO2 selectivity (825). Mixed-gas breakthrough experiments assert the potential of NbOFFIVE-1-Ni as a molecular sieve adsorbent for the effective and energy-efficient removal of carbon dioxide with 99.16 % Xe recovery. Absolute CO2/Xe separation in NbOFFIVE-1-Ni makes closed-circuit Xe recovery and recycling can be easily realized, demonstrating the potential of NbOFFIVE-1-Ni for important anesthetic gas regeneration under ambient conditions. 相似文献
85.
Xiang Li Guodong Zhang Yunqiu Hua Fucai Cui Xue Sun Jiaxin Liu Hongjie Liu Yanxiao Bi Zhongjie Yue Zhongjun Zhai Haibing Xia Xutang Tao 《Angewandte Chemie (International ed. in English)》2023,62(50):e202315817
Inorganic Bi-based perovskites have shown great potential in X-ray detection for their large absorption to X-rays, diverse low-dimensional structures, and eco-friendliness without toxic metals. However, they suffer from poor carrier transport properties compared to Pb-based perovskites. Here, we propose a mixed-halogen strategy to tune the structural dimensions and optoelectronic properties of Cs3Bi2I9−nBrn (0≤n≤9). Ten centimeter-sized single crystals are successfully grown by the Bridgman technique. Upon doping bromine to zero-dimensional Cs3Bi2I9, the crystal transforms into a two-dimensional structure as the bromine content reaches Cs3Bi2I8Br. Correspondingly, the optoelectronic properties are adjusted. Among these crystals, Cs3Bi2I8Br exhibits negligible ion migration, moderate resistivity, and the best carrier transport capability. The sensitivities in 100 keV hard X-ray detection are 1.33×104 and 1.74×104 μC Gyair−1 cm−2 at room temperature and 75 °C, respectively, which are the highest among all reported bismuth perovskites. Moreover, the lowest detection limit of 28.6 nGyair s−1 and ultralow dark current drift of 9.12×10−9 nA cm−1 s−1 V−1 are obtained owing to the high ionic activation energy. Our work demonstrates that Br incorporation is an effective strategy to enhance the X-ray detection performance by tuning the dimensional and optoelectronic properties. 相似文献
86.
Bize Gao Dr. Quanren Zhu Prof. Dr. Yanhui Yi Yue Li Guoxing Wu Yitong Guo Prof. Dr. Zhaochi Feng Prof. Dr. Hongchen Guo 《欧洲无机化学杂志》2023,26(22):e202200661
The epoxidation of propylene with dilute H2O2 aqueous solution over titanium silicalite-1 (TS-1) zeolite catalyst is a green chemical reaction for propylene oxide (PO) production. Carrying out the reaction in gas-phase can get rid of problems caused by using methanol solvent. This paper reports an attempt of using non-zeolite catalyst for the gas-phase epoxidation. Amorphous Ti/SiO2, obtained by grafting amorphous SiO2 with TCl4 in ethanol solvent in a chemical liquid-phase deposition (CLD) process, has been used as the catalyst. Results show that the CLD Ti/SiO2 with appropriate Si/Ti molar ratio is an active catalyst for gas-phase epoxidation, achieving 9.8 % propylene conversion and 66.9 % PO selectivity with 40.3 % H2O2 utilization, which indicates that this amorphous Ti/SiO2 catalyst deserves extensive studies in the future. 相似文献
87.
Junchen Zhu Kailong Yuan Yue Xie Huabing Liu Huiqing Jin Cuirong Sun Hongru Feng Qi Li Yuanjiang Pan 《Journal of separation science》2023,46(23):2300415
Sucrose esters (SEs) are crucial tobacco smoke flavor precursors and play a significant role in tobacco's functionality. Due to their structural complexity, the separation and analysis of SEs in tobacco remain a major challenge, and massive structures of SEs have not yet been fully identified. In this study, the fractions enriched in SEs were obtained from oriental and flue-cured tobacco through a series of pretreatments, and two types of SEs (Types I and II) were distinguished by liquid chromatography-tandem mass spectrometry (LC-MSn) analysis, with Type II SEs newly characterized in tobacco. Five groups of main SEs were further purified using preparative high-performance LC (HPLC) coupled to an evaporative light scattering detector, and their structures were characterized by nuclear magnetic resonance spectrometry techniques including 1H, 13C, correlation spectroscopy, heteronuclear single quantum correlation, and heteronuclear multiple bond correlation. By combining LC-MSn and nuclear magnetic resonance spectrometry, the structures of eight SE isomers were finally proposed, of which four were newly identified. These findings further enhance the understanding of the structural diversity of SEs in tobacco, serving as a valuable reference for future research on the elucidation, synthesis, and metabolism of SEs. 相似文献
88.
Yue Li Xin-Xin Jiang Hong-Mei Liu Xiao-wei Li Xiao-Jun Luo Xun Liao Yan Zhao 《Journal of separation science》2023,46(14):2300195
The inhibition of tyrosinase is considered to be a common therapeutic strategy for some hyperpigmentation disorders. Screening of tyrosinase inhibitors is of great significance to the treatment of pigmentation diseases. In this study, tyrosinase was covalently immobilized on magnetic multi-walled carbon nanotubes for the first time, and the immobilized tyrosinase was applied for ligand fishing of tyrosinase inhibitors from complex medicinal plants. The immobilized tyrosinase was characterized by transmission electron microscopy, atomic force microscopy, Fourier-transform infrared spectroscopy, vibrating sample magnetometry, and thermo-gravimetric analyzer, which indicated that tyrosinase was immobilized onto magnetic multi-walled carbon nanotubes. The immobilized tyrosinase showed better thermal stability and reusability than the free one. The ligand was fished out from Radix Paeoniae Alba and identified as 1,2,3,4,6-pentagalloylglucose by ultra-performance liquid chromatography-quadrupole time-of-flight high-resolution mass spectrometry. 1,2,3,4,6-pentagalloylglucose was found to be a tyrosinase inhibitor with similar half maximal inhibitory concentration values of 57.13 ± 0.91 μM compared to kojic acid (41.96 ± 0.78 μM). This work not only established a new method for screening tyrosinase inhibitors but also holds considerable potential for exploring the new medicinal value of medicinal plants. 相似文献
89.
Munir Ullah Khan Safir Ullah Khan Xiaohan Cao Muhammad Usman Xinchen Yue Abdul Ghaffar Muhammad Hassan Prof. Chengjian Zhang Prof. Xinghong Zhang 《化学:亚洲杂志》2023,18(1):e202201050
This study demonstrates the superiority of a stable and well-defined heterogeneous cobalt hexacyanocobaltate (Co3[Co(CN)6]2), a typical cobalt Prussian Blue Analogue (CoCo-PBA) that catalyzes the copolymerization of carbonyl sulfide (COS) and propylene oxide (PO) to produce poly(propylene monothiocarbonate)s (PPMTC). The number-average molecular weights of the PPMTC were 66.4 to 139.4 kg/mol, with a polydispersity of 2.0–3.9. The catalyst productivity reached 1040 g polymer/g catalyst (12.0 h). The oxygen-sulfur exchange reaction (O/S ER), which would generate random thiocarbonate and carbonate units, was effectively suppressed, and thus the selectivity of the monothiocarbonate over carbonate linkages was up to >99%. It was shown that no cyclic thiocarbonate byproduct was produced during the heterogeneous catalysis of COS/PO copolymerization using CoCo-PBA as the catalyst. The content of monothiocarbonate and ether units in the copolymer chain could be regulated by tuning the feeding amount of COS. 相似文献
90.
利用电感耦合等离子体原子发射光谱仪( ICP-AES)建立白云石和菱镁石中铝、钙、铁、镁、锰、磷、硅、锶的测定方法。研究了酸体系、温度及消解方式对试样消解的影响,结果表明,使用5 mL盐酸和硝酸混合酸(1:3)-0.75 mL氢氟酸-5 mL水以密闭消解的方式在150 ℃下消解白云石和菱镁石30min,并以2mL饱和硼酸络合多余的氢氟酸,可以得到澄清消解液。通过白云石和菱镁石中铝、钙、铁、镁、锰、磷、硅、锶的谱线干扰情况,选择Al 308.215 nm、Ca 318.127 nm、Fe 261.187 nm、Mg 277.983 nm、Mn 257.61 nm、P 213.618 nm、Si 251.611 nm、Sr 421.552 nm作为分析线,各元素的校准曲线在线性范围内线性关系良好,相关系数均不小于0.999。按照实验方法测定白云石和菱镁石标准物质,各元素结果的相对标准偏差 (RSD, n=6)为0.89~3.19%,测定值与认定值无显著性差异。本方法有效解决了白云石和菱镁石快速有效溶解及准确测定问题。 相似文献