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31.
Fu Yajing Li Ji Wang Hairui Zhang Jiahao Ma Zhijun Yi Qiong Liu Jianwen Wang Shiquan 《Journal of Solid State Electrochemistry》2023,27(9):2523-2531
Journal of Solid State Electrochemistry - FeS2/CoS and FeS2/CoS/C composites were synthesized by solvothermal method and following vapor phase vulcanization at mild temperature with binary oxide... 相似文献
32.
With the gradual depletion of traditional zinc resources, the full use of various non-traditional zinc-containing resources has received intensive attention. However, the efficient recovery of zinc ions with low concentrations remains challenging. Here efficient and continuous recovery of zinc ions in ammoniacal chloride media by a flat supported liquid membrane system is achieved, using Cyanex923 and TBP mixed extractant as the membrane phase. This article discusses the synergistic effect between Aliquat336, Cyanex923 and TBP, the effects of feed pH, total ammonia concentration, Cl− concentration and temperature on Zn(II) transport. 相似文献
33.
Qiong Liu Jingjun Lin Hui Cheng Liling Wei Fuxian Wang 《Angewandte Chemie (International ed. in English)》2023,62(13):e202218720
Photocatalytic conversion of CO2 is of great interest but it often suffers sluggish oxidation half reaction and undesired by-products. Here, we report for the first the simultaneous co-photocatalytic CO2 reduction and ethanol oxidation towards one identical value-added CH3CHO product on a rubidium and potassium co-modified carbon nitride (CN-KRb). The CN-KRb offers a record photocatalytic activity of 1212.3 μmol h−1g−1 with a high selectivity of 93.3 % for CH3CHO production, outperforming all the state-of-art CO2 photocatalysts. It is disclosed that the introduced Rb boosts the *OHCCHO fromation and facilitates the CH3CHO desorption, while K promotes ethanol adsorption and activation. Moreover, the H+ stemming from ethanol oxidation is confirmed to participate in the CO2 reduction process, endowing near ideal overall atomic economy. This work provides a new strategy for effective use of the photoexcited electron and hole for high selective and sustainable conversion of CO2 paired with oxidation reaction into identical product. 相似文献
34.
Dr. Shi Tang Dr. Zhi Wang Yanzi Xu Huili Ma Dr. Jia Wang Dr. Christian Larsen Prof. Dongfeng Dang Prof. Ergang Wang Prof. Ludvig Edman 《Angewandte Chemie (International ed. in English)》2023,62(23):e202302874
The emission efficiency of organic semiconductors (OSCs) often suffers from aggregation caused quenching (ACQ). An elegant solution is aggregation-induced emission (AIE), which constitutes the design of the OSC so that its morphology inhibits quenching π–π interactions and non-radiative motional deactivation. The light-emitting electrochemical cell (LEC) can be sustainably fabricated, but its function depends on motion of bulky ions in proximity of the OSC. It is therefore questionable whether the AIE morphology can be retained during LEC operation. Here, we synthesize two structurally similar OSCs, which are distinguished by that 1 features ACQ while 2 delivers AIE. Interestingly, we find that the AIE-LEC significantly outperforms the ACQ-LEC. We rationalize our finding by showing that the AIE morphology remains intact during LEC operation, and that it can feature appropriately sized free-volume voids for facile ion transport and suppressed non-radiative excitonic deactivation. 相似文献
35.
Dr. Tao Ma Dr. Youxuan Ni Diantao Li Dr. Zhengtai Zha Dr. Song Jin Weijia Zhang Liqun Jia Qiong Sun Dr. Weiwei Xie Prof. Zhanliang Tao Prof. Jun Chen 《Angewandte Chemie (International ed. in English)》2023,62(43):e202310761
Despite carbonate electrolytes exhibiting good stability to sulfurized polyacrylonitrile (SPAN), their chemical incompatibility with lithium (Li) metal anode leads to poor electrochemical performance of Li||SPAN full cells. While the SPAN employs conventional ether electrolytes that suffer from the shuttle effect, leading to rapid capacity fading. Here, we tailor a dilute electrolyte based on a low solvating power ether solvent that is both compatible with SPAN and Li metal. Unlike conventional ether electrolytes, the weakly solvating ether electrolyte enables SPAN to undergo reversibly “solid–solid” conversion. It features an anion–rich solvation structure that allows for the formation of a robust cathode electrolyte interphase on the SPAN, effectively blocking the dissolution of polysulfides into the bulk electrolyte and avoiding the shuttle effect. What's more, the unique electrolyte chemistry endowed Li ions with fast electroplating kinetics and induced high reversibility Li deposition/stripping process from 25 °C to −40 °C. Based on tailored electrolyte, Li||SPAN full cells matched with high loading SPAN cathodes (≈3.6 mAh cm−2) and 50 μm Li foil can operate stably over a wide range of temperatures. Additionally, Li||SPAN pouch cell under lean electrolyte and 5 % excess Li conditions can continuously operate stably for over a month. 相似文献
36.
Santhanamoorthi Nachimuthu Yi-Hui Kuo Dang Hoai Khanh Zhan-Jun Zhu Jyh-Chiang Jiang 《中国化学会会志》2023,70(3):349-358
The ability of the polymer-based graphitic carbon nitride (g-C3N4) as a gas sensor toward NO, NO2, CO, CO2, SO2, SO3, and O2 gasses is assessed using density functional theory (DFT) calculations in terms of energetic and electronic transport characteristics. In particular, this study is aimed to explore the role of zigzag and armchair edges of the g-C3N4 sheet on sensing performances. The electronic properties of adsorption systems, such as Bader charge analysis, band gaps, work function, and density of states (DOS), are used to understand the interaction between the adsorbed gas molecules and the g-C3N4 sheet. Our calculated results indicate that SOx (SO3 and SO2) gasses have higher adsorption energies on the g-C3N4 sheet than other gasses. Furthermore, the transport properties, such as current–voltage (I-V) and resistance-voltage (R-V) curves along the zigzag and armchair directions are calculated using the non-equilibrium Green's function (NEGF) method to understand the performance of the g-C3N4 sheet as a prominent conductive/resistive sensor. The I-V/R-V results indicate that the zigzag g-C3N4 sheet has excellent sensing ability toward SOx gasses at low applied voltages. However, the presence of H2O degrades the sensing performance of the armchair g-C3N4 sheet. Theoretical recovery time has also been calculated to evaluate the reusability of g-C3N4 sheet-based gas sensors. Our results reveal that the zigzag g-C3N4 sheet-based sensing device has a remarkably high sensitivity (>300%) and selectivity toward SOx gasses and has the potential to work in a complex environment. 相似文献
37.
Bo Zhen Xinyue Suo Jun Dang Huilan Yue Yanduo Tao Jia-Jia Wang Li Li Ming-Bao Lin Qi Hou Wei-Ping Wang Xiao-Liang Wang Jian-Dong Jiang Teng-Fei Ji 《中国化学快报》2021,32(7):2338-2341
Hyperterpenoid A (1) and B (2), two pairs of enantiomers, with an unprecedented 6/6/4/6/6 polycyclic skeleton, along with one known compoud hypermonone A (3) were isolated from Hypericum beanii. The racemate (±)-1 and (±)-2 were successfully separated into the two optically pure enantiomers (ee ≥ 99%) using a preparative HPLC system. Their absolute configurations were elucidated by extensive spectroscopic analyses and single-crystal X-ray diffraction method. The related plausible biogenetic pathways were presented. Compound 1-3 showed significant neuroprotective activity and potential anti-inflammatory activity. The result that (+)-2 and (-)-2 presented different anti-inflammatory properties, may lead us to new discovery of structure activity relationship between racemates, enantiomers, and diastereomers, as well as further research regarding the binding of drugs to target proteins. 相似文献
38.
Cong-Luan Tran Thi-Bich-Ngoc Dao Thanh-Nha Tran Dinh-Tri Mai Thi-Minh-Dinh Tran Nguyen-Minh-An Tran Van-Son Dang Thi-Xuyen Vo Thuc-Huy Duong Jirapast Sichaem 《Molecules (Basel, Switzerland)》2021,26(8)
Bioactive-guided phytochemical investigation of Euphorbia antiquorum L. growing in Vietnam led to the isolation of five ent-atisanes, one seco-ent-atisane, and one lathyrane (ingol-type). The structures were elucidated as ent-1α,3α,16β,17-tetrahydroxyatisane (1), ethyl ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylate (2), ent-atisane-3-oxo-16β,17-acetonide (3), ent-3α-acetoxy-16β,17-dihydroxyatisane (4), ent-16β,17-dihydroxyatisane-3-one (5), calliterpenone (6), and ingol 12-acetate (7). Their chemical structures were unambiguously determined by analysis of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) and high resolution mass spectrometry, as well as by comparison with literature data. Among them, 1 is a new compound while 2 is an ethylated artifact of ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylic acid, a new compound. Isolates were evaluated for alpha-glucosidase inhibition. Compound 3 showed the most significant inhibitory activity against alpha-glucosidase with an IC50 value of 69.62 µM. Further study on mechanism underlying yeast alpha-glucosidase inhibition indicated that 3 could retard the enzyme function by noncompetitive. 相似文献
39.
Deng Xi Wu Liling Deng Yunmeng Huang Siqi Sun Mengtian Wang Xiaowu Liu Qiong Li Ming Li Zhi 《Journal of Sol-Gel Science and Technology》2021,100(3):477-488
Journal of Sol-Gel Science and Technology - This work presents a facile synthesis approach of methyltriethoxysilane (MTES) based aerogels using pure water as the only solvent, and the effects of... 相似文献
40.
Dang Huu Phuc Ha Thanh Tung Van-Cuong Nguyen My Hanh Nguyen Thi 《Molecules (Basel, Switzerland)》2021,26(10)
In this study, TiO2/CdS/CdxCu1−xSe, TiO2/CdS/CdxMn1−xSe, and TiO2/CdS/CdxAg2−2xSe thin films were synthesized by chemical bath deposition for the fabrication of photoanode in quantum-dot-sensitized solar cells. As a result, the structural properties of the thin films have been studied by X-ray diffraction, which confirmed the zinc Blende structure in the samples. The optical films were researched by their experimental absorption spectra with different doping concentrations. Those results were combined with the Tauc correlation to estimate the absorption density, the band gap energy, valence band and conduction band positions, steepness parameter, and electron–phonon interaction. Furthermore, the electrical features, electrochemical impedance spectrum and photocurrent density curves were carried out. The result was used to explain the enhancing performance efficiency. 相似文献