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101.
Longbin Li Xiannong Tang Senhe Huang Dr. Chenbao Lu Prof. Dirk Lützenkirchen-Hecht Prof. Kai Yuan Prof. Xiaodong Zhuang Prof. Yiwang Chen 《Angewandte Chemie (International ed. in English)》2023,62(22):e202301642
Iron phthalocyanine-based polymers (PFePc) are attractive noble-metal-free candidates for catalyzing oxygen reduction reaction (ORR). However, the low site-exposure degree and poor electrical conductivity of bulk PFePc restricted their practical applications. Herein, laminar PFePc nanosheets covalently and longitudinally linked to graphene (3D-G-PFePc) was prepared. Such structural engineering qualifies 3D-G-PFePc with high site utilization and rapid mass transfer. Thence, 3D-G-PFePc demonstrates efficient ORR performance with a high specific activity of 69.31 μA cm−2, a high mass activity of 81.88 A g−1, and a high turnover frequency of 0.93 e s−1 site−1 at 0.90 V vs. reversible hydrogen electrode in O2-saturated 0.1 M KOH, outperforming the lamellar PFePc wrapped graphene counterpart. Systematic electrochemical analyses integrating variable-frequency square wave voltammetry and in situ scanning electrochemical microscopy further underline the rapid kinetics of 3D-G-PFePc towards ORR. 相似文献
102.
Jiashen Zhou Lin Zhang Yiran Wang Wenyan Song Yuzhou Huang Yajuan Mu Werner Schmitz Shu-Yu Zhang Houwen Lin Hong-Zhuan Chen Fei Ye Liang Zhang 《Angewandte Chemie (International ed. in English)》2023,62(46):e202313109
The short-chain dehydrogenase/reductase (SDR) superfamily members acyl-ACP reductases FabG and FabI are indispensable core enzymatic modules and catalytic orientation controllers in type-II fatty acid biosynthesis. Herein, we report their distinct substrate allosteric recognition and enantioselective reduction mechanisms. FabG achieves allosteric regulation of ACP and NADPH through ACP binding across two adjacent FabG monomers, while FabI follows an irreversible compulsory order of substrate binding in that NADH binding must precede that of ACP on a discrete FabI monomer. Moreover, FabG and FabI utilize a backdoor residue Phe187 or a “rheostat” α8 helix for acyl chain length selection, and their corresponding triad residues Ser142 or Tyr145 recognize the keto- or enoyl-acyl substrates, respectively, facilitating initiation of nucleophilic attack by NAD(P)H. The other two triad residues (Tyr and Lys) mediate subsequent proton transfer and (R)-3-hydroxyacyl- or saturated acyl-ACP production. 相似文献
103.
Dr. Jian Li Lei Zhu Prof. Dr. Chen-Ho Tung Prof. Dr. Li-Zhu Wu 《Angewandte Chemie (International ed. in English)》2023,62(22):e202301384
Graphdiyne (GDY) with a direct band gap, excellent carrier mobility and uniform pores, is regarded as a promising photocatalytic material for solar energy conversion, while the research on GDY in photocatalysis is a less developed field. Herein, the distinctive structure, adjustable band gap, and electronic properties of GDY for photocatalysis is firstly summarized. The construction and progress of GDY-based photocatalysts for solar energy conversion, including H2 evolution reaction (HER), CO2 reduction reaction (CO2RR) and N2 reduction reaction (NRR) are then elaborated. At last, the challenges and perspectives in developing GDY-based photocatalysts for solar fuel production are discussed. It is anticipated that a timely Minireview will be helpful for rapid progress of GDY in solar energy conversion. 相似文献
104.
Shengpeng Mo Xinya Zhao Shuangde Li Lili Huang Xin Zhao Quanming Ren Mingyuan Zhang Ruosi Peng Yanan Zhang Xiaobin Zhou Yinming Fan Prof. Qinglin Xie Prof. Yanbing Guo Prof. Daiqi Ye Prof. Yunfa Chen 《Angewandte Chemie (International ed. in English)》2023,62(50):e202313868
Solar-to-chemical energy conversion under weak solar irradiation is generally difficult to meet the heat demand of CO2 reduction. Herein, a new concentrated solar-driven photothermal system coupling a dual-metal single-atom catalyst (DSAC) with adjacent Ni−N4 and Fe−N4 pair sites is designed for boosting gas-solid CO2 reduction with H2O under simulated solar irradiation, even under ambient sunlight. As expected, the (Ni, Fe)−N−C DSAC exhibits a superior photothermal catalytic performance for CO2 reduction to CO (86.16 μmol g−1 h−1), CH4 (135.35 μmol g−1 h−1) and CH3OH (59.81 μmol g−1 h−1), which are equivalent to 1.70-fold, 1.27-fold and 1.23-fold higher than those of the Fe−N−C catalyst, respectively. Based on theoretical simulations, the Fermi level and d-band center of Fe atom is efficiently regulated in non-interacting Ni and Fe dual-atom pair sites with electronic interaction through electron orbital hybridization on (Ni, Fe)−N−C DSAC. Crucially, the distance between adjacent Ni and Fe atoms of the Ni−N−N−Fe configuration means that the additional Ni atom as a new active site contributes to the main *COOH and *HCO3 dissociation to optimize the corresponding energy barriers in the reaction process, leading to specific dual reaction pathways (COOH and HCO3 pathways) for solar-driven photothermal CO2 reduction to initial CO production. 相似文献
105.
Jing-Xiang Wang Dr. Avery C. Vilbert Dr. Chang Cui Dr. Evan N. Mirts Lucas H. Williams Wantae Kim Prof. Dr. Y. Jessie Zhang Prof. Dr. Yi Lu 《Angewandte Chemie (International ed. in English)》2023,62(52):e202314019
The key to type 1 copper (T1Cu) function lies in the fine tuning of the CuII/I reduction potential (E°′T1Cu) to match those of its redox partners, enabling efficient electron transfer in a wide range of biological systems. While the secondary coordination sphere (SCS) effects have been used to tune E°′T1Cu in azurin over a wide range, these principles are yet to be generalized to other T1Cu-containing proteins to tune catalytic properties. To this end, we have examined the effects of Y229F, V290N and S292F mutations around the T1Cu of small laccase (SLAC) from Streptomyces coelicolor to match the high E°′T1Cu of fungal laccases. Using ultraviolet-visible absorption and electron paramagnetic resonance spectroscopies, together with X-ray crystallography and redox titrations, we have probed the influence of SCS mutations on the T1Cu and corresponding E°′T1Cu. While minimal and small E°′T1Cu increases are observed in Y229F- and S292F-SLAC, the V290N mutant exhibits a major E°′T1Cu increase. Moreover, the influence of these mutations on E°′T1Cu is additive, culminating in a triple mutant Y229F/V290N/S292F-SLAC with the highest E°′T1Cu of 556 mV vs. SHE reported to date. Further activity assays indicate that all mutants retain oxygen reduction reaction activity, and display improved catalytic efficiencies (kcat/KM) relative to WT-SLAC. 相似文献
106.
Liangxu Lin Liang Huang Chang Wu Yu Gao Naihua Miao Chao Wu Aaron T. Marshall Yi Zhao Jiazhao Wang Jun Chen Shixue Dou Gordon G. Wallace Wei Huang 《Angewandte Chemie (International ed. in English)》2023,62(49):e202315182
The exploration of inexpensive and efficient catalysts for oxygen reduction reaction (ORR) is crucial for chemical and energy industries. Carbon materials have been proved promising with different catalysts enabling 2 and 4e− ORR. Nevertheless, their ORR activity and selectivity is still complex and under debate in many cases. Many structures of these active carbon materials are also chemically unstable for practical implementations. Unlike the well-discussed structures, this work presents a strategy to promote efficient and stable 2e− ORR of carbon materials through the synergistic effect of lattice distortion and H-passivation (on the distorted structure). We show how these structures can be formed on carbon cloth, and how the reproducible chemical adsorption can be realized on these structures for efficient and stable H2O2 production. The work here gives not only new understandings on the 2e− ORR catalysis, but also the robust catalyst which can be directly used in industry. 相似文献
107.
Dr. Hong-Tao Zhang Dr. Fei Xie Yu-Hua Guo Yao Xiao Prof. Dr. Ming-Tian Zhang 《Angewandte Chemie (International ed. in English)》2023,62(48):e202310775
We report herein the first nonheme CuFe oxygen reduction catalyst ([CuII(bpbp)(μ-OAc)2FeIII]2+, CuFe−OAc ), which serves as a functional model of cytochrome c oxidase and can catalyze oxygen reduction to water with a turnover frequency of 2.4×103 s−1 and selectivity of 96.0 % in the presence of Et3NH+. This performance significantly outcompetes its homobimetallic analogues (2.7 s−1 of CuCu−OAc with %H2O2 selectivity of 98.9 %, and inactive of FeFe−OAc ) under the same conditions. Structure-activity relationship studies, in combination with density functional theory calculation, show that the CuFe center efficiently mediates O−O bond cleavage via a CuII(μ-η1 : η2-O2)FeIII peroxo intermediate in which the peroxo ligand possesses distinctive coordinating and electronic character. Our work sheds light on the nature of Cu/Fe heterobimetallic cooperation in oxygen reduction catalysis and demonstrates the potential of this synergistic effect in the design of nonheme oxygen reduction catalysts. 相似文献
108.
Xiaoliang Lu Jinzhi Zhou Jinxiu Zhao Prof. Dan Wu Xuejing Liu Prof. Xiang Ren Prof. Qin Wei Prof. Huangxian Ju 《Chemphyschem》2023,24(20):e202300536
The electrocatalytic nitrate reduction reaction (NO3−RR) enables the reduction of nitrate to ammonium ions under ambient conditions. It was considered as an alternative reaction for the production of ammonia (NH3) in recent years. In this paper, we report that the Fe doping CoS2 nanoarrays can effectively catalyze the formation of NH3 from nitrate (NO3−) under ambient conditions. This is mainly due to the increase of the NO3− reaction active site by Fe doping and the porous nanostructure of the catalyst, which greatly improves the catalytic activity. Specifically, at −0.9 V vs. RHE, the NH3 yield rate (RNH3) of Fe−CoS2/CC is 17.8×10−2 mmol h−1 cm−2 with Faraday Efficiency (FE) of 88.93 %. Besides, such catalyst shows good durability and catalytic stability, which provides the possibility for the future application of electrocatalytic NH3 production. 相似文献
109.
Vipul Desai Dr. Vinay S. Sharma Suryajit L. Rathod Dr. Anuj S. Sharma Hitendra A. Mali Dr. Rutesh R. Shah Prof. Pranav S. Shrivastav 《Chemphyschem》2023,24(9):e202200803
Four new azo-based supramolecular materials containing thiacalixarene core substituted by variable alkoxy groups ( TFA1 – TFA4 ) have been designed and synthesized for the mesomorphic and photoswitching properties. The liquid crystalline behavior were accomplished by using DSC, POM, and XRD studies. All azo-based thiacalixarene based materials with short and higher chain length display columnar hexagonal mesophase with broad temperature range. The thermal behavior of all the materials was investigated by DSC and TGA study. The structural and conformational study of the lower rim functionalized materials was confirmed by using different techniques. These thiacalixarene moulded liquid crystalline compounds shows columnar self-assembly type behavior and higher thermal stability. The introduction of bi-substituted azo-ester network towards the lower rim of thiacalixarene core has impact on the electron delocalization and liquid crystalline properties. The photoswitching properties suggested cis and trans azo-isomerization under radiation of UV light and higher thermal back relaxation time. The mesogenic behaviour of compound TFA2 and TFA4 were demolished by the influence of cis and trans isomerization. The structure-property correlation is studied to understand the variation in mesogenic properties with the substitution of variable alkoxy side chain. 相似文献
110.
Fansheng Ning Heng Zhu Huijiao Yan Jiguo Liu Shahid Aziz Hidayat Hussain Xiangyun Song Lei Xie Zhaoqing Meng Guiyun Cao Daijie Wang 《Journal of separation science》2023,46(16):2300053
In this work, the preparative separation of quinolyridine alkaloids from seeds of T. lanceolata by conventional and pH-zone-refining counter-current chromatography. Traditional counter-current chromatography separation was performed by a flow-rate changing strategy with a solvent system of ethyl acetate-n-butanol-water (1:9:10, v/v) and 200 mg sample loading. Meanwhile, the pH-zone-refining mode was adopted for separating 2.0 g crude alkaloid extracts with the chloroform-methanol-water (4:3:3, v/v) solvent system using the stationary and mobile phases of 40 mM hydrochloric acid and 10 mM triethylamine. Finally, six compounds, including N-formylcytisine (two conformers) ( 1 ), N-acetycytisine (two conformers) ( 2 ), (-)-cytisine ( 3 ), 13-β-hydroxylthermopsine ( 4 ), N-methylcytisine ( 5 ), and thermopsine ( 6 ) were successfully obtained in the two counter-current chromatography modes with the purities over 96.5%. Moreover, we adopted nuclear magnetic resonance and mass spectrometry for structural characterization. Based on the obtained findings, the pH-zone-refining mode was the efficient method to separate quinolyridine alkaloids relative to the traditional mode. 相似文献