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991.
Henri de Maissin Philipp R. Groß Obaid Mohiuddin Dr. Moritz Weigt Luca Nagel Marvin Herzog Zirun Wang Robert Willing Dr. Wilfried Reichardt Dr. Martin Pichotka Dr. Lisa Heß Prof. Dr. Thomas Reinheckel Prof. Dr. Henning J. Jessen Prof. Dr. Robert Zeiser Prof. Dr. Michael Bock Prof. Dominik von Elverfeldt Prof. Dr. Maxim Zaitsev Dr. Sergey Korchak Dr. Stefan Glöggler Prof. Dr. Jan-Bernd Hövener Prof. Dr. Eduard Y. Chekmenev Prof. Dr. Franz Schilling Dr. Stephan Knecht Dr. Andreas B. Schmidt 《Angewandte Chemie (International ed. in English)》2023,62(36):e202306654
992.
Jiahui Xian Suisheng Li Hui Su Peisen Liao Shihan Wang Runan Xiang Yawei Zhang Prof. Qinghua Liu Prof. Guangqin Li 《Angewandte Chemie (International ed. in English)》2023,62(30):e202306726
The conversion of industrial exhaust gases of nitrogen oxides into high-value products is significantly meaningful for global environment and human health. And green synthesis of amino acids is vital for biomedical research and sustainable development of mankind. Herein, we demonstrate an innovative approach for converting nitric oxide (NO) to a series of α-amino acids (over 13 kinds) through electrosynthesis with α-keto acids over self-standing carbon fiber membrane with CoFe alloy. The essential leucine exhibits a high yield of 115.4 μmol h−1 corresponding a Faradaic efficiency of 32.4 %, and gram yield of products can be obtained within 24 hours in lab as well as an ultra-long stability (>240 h) of the membrane catalyst, which could convert NO into NH2OH rapidly attacking α-keto acid and subsequent hydrogenation to form amino acid. In addition, this method is also suitable for other nitrogen sources including gaseous NO2 or liquidus NO3− and NO2−. Therefore, this work not only presents promising prospects for converting nitrogen oxides from exhaust gas and nitrate-laden waste water into high-value products, but also has significant implications for synthetizing amino acids in biomedical and catalytic science. 相似文献
993.
Dr. Fangping Ren Ji Xian Zhaowei Jia Zhichun Chen Hongjun Fu Prof. Dr. Rui Wang Prof. Dr. Wen-Dao Chu Prof. Dr. Xiaobo Pan Jincai Wu 《Angewandte Chemie (International ed. in English)》2023,62(44):e202306759
To synthesize high molecular weight poly(phenolic ester) via a living ring-opening polymerization (ROP) of cyclic phenolic ester monomers remains a critical challenge due to serious transesterification and back-biting reactions. Both phenolic ester bonds in monomer and polymer chains are highly active, and it is difficult so far to distinguish them. In this work, an unprecedented selectively bifunctional catalytic system of tetra-n-butylammonium chloride (TBACl) was discovered to mediate the syntheses of high molecular weight salicylic acid-based copolyesters via a living ROP of salicylate cyclic esters (for poly(salicylic methyl glycolide) (PSMG), Mn=361.8 kg/mol, Ð<1.30). Compared to previous catalysis systems, the side reactions were suppressed remarkably in this catalysis system because phenolic ester bond in monomer can be selectively cleaved over that in polymer chains during ROP progress. Mechanistic studies reveal that the halide anion and alkyl-quaternaryammonium cation work synergistically, where the alkyl-quaternaryammonium cation moiety interacts with the carbonyl group of substrates via non-classical hydrogen bonding. Moreover, these salicylic acid-based copolyesters can be recycled to dimeric monomer under solution condition, and can be recycled to original monomeric monomers without catalyst under sublimation condition. 相似文献
994.
Xiangyu Li Ailing Tang Helin Wang Zongtao Wang Mengzhen Du Qiang Guo Qing Guo Erjun Zhou 《Angewandte Chemie (International ed. in English)》2023,62(39):e202306847
A third component featuring a planar backbone structure similar to the binary host molecule has been the preferred ingredient for improving the photovoltaic performance of ternary organic solar cells (OSCs). In this work, we explored a new avenue that introduces 3D-structured molecules as guest acceptors. Spirobifluorene (SF) is chosen as the core to combine with three different terminal-modified (rhodanine, thiazolidinedione, and dicyano-substituted rhodanine) benzotriazole (BTA) units, affording three four-arm molecules, SF-BTA1, SF-BTA2, and SF-BTA3, respectively. After adding these three materials to the classical system PM6 : Y6, the resulting ternary devices obtained ultra-high power-conversion efficiencies (PCEs) of 19.1 %, 18.7 %, and 18.8 %, respectively, compared with the binary OSCs (PCE=17.4 %). SF-BTA1-3 can work as energy donors to increase charge generation via energy transfer. In addition, the charge transfer between PM6 and SF-BTA1-3 also acts to enhance charge generation. Introducing SF-BTA1-3 could form acceptor alloys to modify the molecular energy level and inhibit the self-aggregation of Y6, thereby reducing energy loss and balancing charge transport. Our success in 3D multi-arm materials as the third component shows good universality and brings a new perspective. The further functional development of multi-arm materials could make OSCs more stable and efficient. 相似文献
995.
Ning Ling Jiguang Zhang Meng Wang Zhen Wang Ziyu Mi Surani Bin Dolmanan Mingsheng Zhang Bingqing Wang Wan Ru Leow Jia Zhang Yanwei Lum 《Angewandte Chemie (International ed. in English)》2023,62(36):e202308782
Electrochemical CO2 reduction (CO2R) in acidic media with Cu-based catalysts tends to suffer from lowered selectivity towards multicarbon products. This could in principle be mitigated using tandem catalysis, whereby the *CO coverage on Cu is increased by introducing a CO generating catalyst (e.g. Ag) in close proximity. Although this has seen significant success in neutral/alkaline media, here we report that such a strategy becomes impeded in acidic electrolyte. This was investigated through the co-reduction of 13CO2/12CO mixtures using a series of Cu and CuAg catalysts. These experiments provide strong evidence for the occurrence of tandem catalysis in neutral media and its curtailment under acidic conditions. Density functional theory simulations suggest that the presence of H3O+ weakens the *CO binding energy of Cu, preventing effective utilization of tandem-supplied CO. Our findings also provide other unanticipated insights into the tandem catalysis reaction pathway and important design considerations for effective CO2R in acidic media. 相似文献
996.
Guangming Wang Shunhua Chen Qiwei Duan Fenfei Wei Prof. Sen Lin Prof. Zailai Xie 《Angewandte Chemie (International ed. in English)》2023,62(38):e202307470
Borocarbonitride (BCN) materials are newly developed oxidative dehydrogenation catalysts that can efficiently convert alkanes to alkenes. However, BCN materials tend to form bulky B2O3 due to over-oxidation at the high reaction temperature, resulting in significant deactivation. Here, we report a series of super stable BCN nanosheets for the oxidative dehydrogenation of propane (ODHP) reaction. The catalytic performance of the BCN nanosheets can be easily regulated by changing the guanine dosage. The control experiment and structural characterization indicate that the introduction of a suitable amount of carbon could prevent the formation of excessive B2O3 from BCN materials and maintain the 2D skeleton at a high temperature of 520 °C. The best-performing catalyst BCN exhibits 81.9 % selectivity towards olefins with a stable propane conversion of 35.8 %, and the propene productivity reaches 16.2 mmol h−1 g−1, which is much better than hexagonal BN (h-BN) catalysts. Density functional theory calculation results show that the presence of dispersed rather than aggregated carbon atoms can significantly affect the electronic microenvironment of h-BN, thereby boosting the catalytic activity of BCN. 相似文献
997.
Jiaqian Zhou Peiran Xie Chao Wang Tieyuan Bian Dr. Jian Chen Dr. Yang Liu Zhu Guo Congcong Chen Xin Pan Prof. Dr. Min Luo Prof. Dr. Jun Yin Prof. Dr. Lingling Mao 《Angewandte Chemie (International ed. in English)》2023,62(35):e202307646
Double perovskites (DP) have attracted extensive attention due to their rich structures and wide application prospects in the field of optoelectronics. Here, we report 15 new Bi-based double perovskite derived halides with the general formula of A2BBiX6 (A=organic cationic ligand, B=K or Rb, X=Br or I). These materials are synthesized using organic ligands to coordinate with metal ions with a sp3 oxygen, and diverse structure types have been obtained with distinct dimensionalities and connectivity modes. The optical band gaps of these phases can be tuned by changing the halide, the organic ligand and the alkali metal, varying from 2.0 to 2.9 eV. The bromide phases exhibit increasing photoluminescence (PL) intensity with decreasing temperature, while the PL intensity of iodide phases changes nonmonotonically with temperature. Because the majority of these phases are non-centrosymmetric, second harmonic generation (SHG) responses are also measured for selected non-centrosymmetric materials, showing different particle-size-dependent trends. Our findings give rise to a series of new structural types to the DP family, and provide a powerful synthetic handle for symmetry breaking. 相似文献
998.
Rui Liu Meng-Lan Shen Lian-Feng Fan Xiao-Le Zhou Pu-Sheng Wang Liu-Zhu Gong 《Angewandte Chemie (International ed. in English)》2023,62(4):e202211631
Allylamines are important building blocks in the synthesis of bioactive compounds. The direct coupling of allylic C−H bonds and commonly available amines is a major synthetic challenge. An allylic C−H amination of 1,4-dienes has been accomplished by palladium catalysis. With aromatic amines, branch-selective allylic aminations are favored to generate thermodynamically unstable Z-allylamines. In addition, more basic aliphatic cyclic amines can also engage in the reaction, but linear dienyl allylic amines are the major products. 相似文献
999.
Taotao Wang Li Zhang Jinbao Wu Prof. Muqing Chen Prof. Shangfeng Yang Prof. Yalin Lu Prof. Pingwu Du 《Angewandte Chemie (International ed. in English)》2023,62(40):e202311352
A few-layer fullerene network possesses several advantageous characteristics, including a large surface area, abundant active sites, high charge mobility, and an appropriate band gap and band edge for solar water splitting. Herein, we report for the first time that the few-layer fullerene network shows interesting photocatalytic performance in pure water splitting into H2 and H2O2 in the absence of any sacrificial reagents. Under optimal conditions, the H2 and H2O2 evolution rates can reach 91 and 116 μmol g−1 h−1, respectively, with good stability. This work demonstrates the novel application of the few-layer fullerene network in the field of energy conversion. 相似文献
1000.
Qiao Zhang Hsin Jung Tsai Fuhua Li Zhiming Wei Qinye He Dr. Jie Ding Yuhang Liu Zih-Yi Lin Xiaoju Yang Dr. Zhaoyang Chen Prof. Fangxin Hu Prof. Xuan Yang Prof. Qing Tang Prof. Hong Bin Yang Prof. Sung-Fu Hung Prof. Yueming Zhai 《Angewandte Chemie (International ed. in English)》2023,62(44):e202311550
Single-atom catalysts exhibit superior CO2-to-CO catalytic activity, but poor kinetics of proton-coupled electron transfer (PCET) steps still limit the overall performance toward the industrial scale. Here, we constructed a Fe−P atom paired catalyst onto nitrogen doped graphitic layer (Fe1/PNG) to accelerate PCET step. Fe1/PNG delivers an industrial CO current of 1 A with FECO over 90 % at 2.5 V in a membrane-electrode assembly, overperforming the CO current of Fe1/NG by more than 300 %. We also decrypted the synergistic effects of the P atom in the Fe−P atom pair using operando techniques and density functional theory, revealing that the P atom provides additional adsorption sites for accelerating water dissociation, boosting the hydrogenation of CO2, and enhancing the activity of CO2 reduction. This atom-pair catalytic strategy can modulate multiple reactants and intermediates to break through the inherent limitations of single-atom catalysts. 相似文献