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71.
Dr. Wei-Hua Deng Prof. Qiao-Hong Li Jie Chen Chuan-Zhe Wang Dr. Zhi-Hua Fu Dr. Xiao-Liang Ye Prof. Guan-E Wang Prof. Gang Xu 《Angewandte Chemie (International ed. in English)》2023,62(31):e202305977
The electronic conductivity (EC) of metal–organic frameworks (MOFs) is sensitive to strongly oxidizing guest molecules. Water is a relatively mild species, however, the effect of H2O on the EC of MOFs is rarely reported. We explored the effect of H2O on the EC in the MOFs (NH2)2-MIL-125 and its derivatives with experimental and theoretical investigations. Unexpectedly, a large EC increase of 107 on H2SO4@(NH2)2-MIL-125 by H2O was observed. Brønsted acid–base pairs formed with the −NH2 groups, and H2SO4 played an important role in promoting the charge transfer from H2O to the MOF. Based on H2SO4@(NH2)2-MIL-125, a high-performance chemiresistive humidity sensor was developed with the highest sensitivity, broadest detection range, and lowest limit of detection amongst all reported sensing materials to date. This work not only demonstrated that H2O can remarkably influence the EC of MOFs, but it also revealed that post-modification of the structure of MOFs could enhance the influence of the guest molecule on their EC to design high-performance sensing materials. 相似文献
72.
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
73.
Xin Feng Dr. Kejun Bu Teng Liu Songhao Guo Zongdong Sun Tonghuan Fu Yongshan Xu Dr. Kailang Liu Dr. Sijie Yang Dr. Yinghe Zhao Prof. Huiqiao Li Prof. Xujie Lü Prof. Tianyou Zhai 《Angewandte Chemie (International ed. in English)》2023,62(9):e202217238
The unique intermolecular van der Waals force in emerging two-dimensional inorganic molecular crystals (2DIMCs) endows them with highly tunable structures and properties upon applying external stimuli. Using high pressure to modulate the intermolecular bonding, here we reveal the highly tunable charge transport behavior in 2DIMCs for the first time, from an insulator to a semiconductor. As pressure increases, 2D α-Sb2O3 molecular crystal undergoes three isostructural transitions, and the intermolecular bonding enhances gradually, which results in a considerably decreased band gap by 25 % and a greatly enhanced charge transport. Impressively, the in situ resistivity measurement of the α-Sb2O3 flake shows a sharp drop by 5 orders of magnitude in 0–3.2 GPa. This work sheds new light on the manipulation of charge transport in 2DIMCs and is of great significance for promoting the fundamental understanding and potential applications of 2DIMCs in advanced modern technologies. 相似文献
74.
Wen-Yan Xu Zhe-Yuan Xu Ze-Kuan Zhang Tian-Jun Gong Yao Fu 《Angewandte Chemie (International ed. in English)》2023,62(40):e202310125
Divergent synthesis of fluorine-containing scaffolds starting from a suite of raw materials is an intriguing topic. Herein, we report the solvent-controlled rhodium-catalyzed tunable arylation of 1-bromo-2,2-difluoroethylene. The selection of the reaction solvents provides switchable defluorinated or debrominated arylation from readily available feedstock resources (both arylboronic acids/esters and 1-bromo-2,2-difluoroethylene are commercially available). This switch is feasible because of the difference in coordination ability between the solvent (CH2Cl2 or CH3CN) and the rhodium center, resulting in different olefin insertion. This protocol allows the convenient synthesis of monofluoroalkenes and gem-difluoroalkenes, both of which are important scaffolds in the fields of medicine and materials. Moreover, this newly developed solvent-regulated reaction system can be applied to the site-selective dechlorinated arylation of trichloroethylene. Overall, this study provides a useful strategy for the divergent synthesis of fluorine-containing scaffolds and provides insight into the importance of solvent selection in catalytic reactions. 相似文献
75.
Youwen Rong Dr. Tianfu Liu Jiaqi Sang Dr. Rongtan Li Dr. Pengfei Wei Dr. Hefei Li Dr. Aiyi Dong Prof. Dr. Li Che Prof. Dr. Qiang Fu Prof. Dr. Dunfeng Gao Prof. Dr. Guoxiong Wang 《Angewandte Chemie (International ed. in English)》2023,62(45):e202309893
Electrochemically converting CO2 to valuable chemicals holds great promise for closing the anthropogenic carbon cycle. Owing to complex reaction pathways and shared rate-determining steps, directing the selectivity of CO2/CO electrolysis to a specific multicarbon product is very challenging. We report here a strategy for highly selective production of acetate from CO electrolysis by constructing metal-organic interfaces. We demonstrate that the Cu-organic interfaces constructed by in situ reconstruction of Cu complexes show very impressive acetate selectivity, with a high Faradaic efficiency of 84.2 % and a carbon selectivity of 92.1 % for acetate production, in an alkaline membrane electrode assembly electrolyzer. The maximum acetate partial current density and acetate yield reach as high as 605 mA cm−2 and 63.4 %, respectively. Thorough structural characterizations, control experiments, operando Raman spectroscopy measurements, and density functional theory calculation results indicate that the Cu-organic interface creates a favorable reaction microenvironment that enhances *CO adsorption, lowers the energy barrier for C−C coupling, and facilitates the formation of CH3COOH over other multicarbon products, thus rationalizing the selective acetate production. 相似文献
76.
Hui Luo Dr. Kejun Bu Dr. Yanfeng Yin Dong Wang Cuimi Shi Songhao Guo Tonghuan Fu Jiayuan Liang Bingyan Liu Dr. Dongzhou Zhang Prof. Liang-Jin Xu Prof. Qingyang Hu Prof. Yang Ding Prof. Shengye Jin Prof. Wenge Yang Prof. Biwu Ma Prof. Xujie Lü 《Angewandte Chemie (International ed. in English)》2023,62(37):e202304494
Low-dimensional (low-D) organic metal halide hybrids (OMHHs) have emerged as fascinating candidates for optoelectronics due to their integrated properties from both organic and inorganic components. However, for most of low-D OMHHs, especially the zero-D (0D) compounds, the inferior electronic coupling between organic ligands and inorganic metal halides prevents efficient charge transfer at the hybrid interfaces and thus limits their further tunability of optical and electronic properties. Here, using pressure to regulate the interfacial interactions, efficient charge transfer from organic ligands to metal halides is achieved, which leads to a near-unity photoluminescence quantum yield (PLQY) at around 6.0 GPa in a 0D OMHH, [(C6H5)4P]2SbCl5. In situ experimental characterizations and theoretical simulations reveal that the pressure-induced electronic coupling between the lone-pair electrons of Sb3+ and the π electrons of benzene ring (lp-π interaction) serves as an unexpected “bridge” for the charge transfer. Our work opens a versatile strategy for the new materials design by manipulating the lp-π interactions in organic–inorganic hybrid systems. 相似文献
77.
Yibo Wang Pengyu Meng Zhaohui Yang Dr. Min Jiang Dr. Jian Yang Dr. Huanxin Li Prof. Jiao Zhang Prof. Baode Sun Prof. Chaopeng Fu 《Angewandte Chemie (International ed. in English)》2023,62(28):e202304229
Highly-active and low-cost bifunctional electrocatalysts for oxygen reduction and evolution are essential in rechargeable metal-air batteries, and single atom catalysts with Fe−N−C are promising candidates. However, the activity still needs to be boosted, and the origination of spin-related oxygen catalytic performance is still uncertain. Herein, an effective strategy to regulate local spin state of Fe−N−C through manipulating crystal field and magnetic field is proposed. The spin state of atomic Fe can be regulated from low spin to intermediate spin and to high spin. The cavitation of dxz and dyz orbitals of high spin FeIII can optimize the O2 adsorption and promote the rate-determining step (*O2 to *OOH). Benefiting from these merits, the high spin Fe−N−C electrocatalyst displays the highest oxygen electrocatalytic activities. Furthermore, the high spin Fe−N−C-based rechargeable zinc-air battery displays a high power density of 170 mW cm−2 and good stability. 相似文献
78.
Jianwu Tian Bowen Li Fu Zhang Zhuo Yao Wentao Song Yufu Tang Yuan Ping Bin Liu 《Angewandte Chemie (International ed. in English)》2023,62(46):e202307288
The phototoxicity of photosensitizers (PSs) pre and post photodynamic therapy (PDT), and the hypoxic tumor microenvironment are two major problems limiting the application of PDT. While activatable PSs can successfully address the PS phototoxicity pre PDT, and type I PS can generate reactive oxygen species (ROS) effectively in hypoxic environment, very limited approaches are available for addressing the phototoxicity post PDT. There is virtually no solution available to address all these issues using a single design. Herein, we propose a proof-of-concept on-demand switchable photosensitizer with quenched photosensitization pre and post PDT, which could be activated only in tumor hypoxic environment. Particularly, a hypoxia-normoxia cycling responsive type I PS TPFN-AzoCF3 was designed to demonstrate the concept, which was further formulated into TPFN-AzoCF3 nanoparticles (NPs) using DSPE-PEG-2000 as the encapsulation matrix. The NPs could be activated only in hypoxic tumors to generate type I ROS during PDT treatment, but remain non-toxic in normal tissues, pre or after PDT, thus minimizing side effects and improving the therapeutic effect. With promising results in in vitro and in vivo tumor treatment, this presented strategy will pave the way for the design of more on-demand switchable photosensitizers with minimized side effects in the future. 相似文献
79.
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
80.
Hongpu Huang Dr. Kai Liu Dr. Fulin Yang Junlin Cai Shupeng Wang Weizhen Chen Dr. Qiuxiang Wang Dr. Luhong Fu Prof. Zhaoxiong Xie Prof. Shuifen Xie 《Angewandte Chemie (International ed. in English)》2023,62(52):e202315752
Breaking atomic monogeneity of catalyst surfaces is promising for constructing synergistic active centers to cope with complex multi-step catalytic reactions. Here, we report a defect-derived strategy for creating surface phosphorous vacancies (P-vacancies) on nanometric Rh2P electrocatalysts toward drastically boosted electrocatalysis for alkaline hydrogen oxidation reaction (HOR). This strategy disrupts the monogeneity and atomic regularity of the thermodynamically stable P-terminated surfaces. Density functional theory calculations initially verify that the competitive adsorption behavior of Had and OHad on perfect P-terminated Rh2P{200} facets (p-Rh2P) can be bypassed on defective Rh2P{200} surfaces (d-Rh2P). The P-vacancies enable the exposure of sub-surface Rh atoms to act as exclusive H adsorption sites. Therein, the Had cooperates with the OHad on the peripheral P-sites to effectively accelerate the alkaline HOR. Defective Rh2P nanowires (d-Rh2P NWs) and perfect Rh2P nanocubes (p-Rh2P NCs) are then elaborately synthesized to experimentally represent the d-Rh2P and p-Rh2P catalytic surfaces. As expected, the P-vacancy-enriched d-Rh2P NWs catalyst exhibits extremely high catalytic activity and outstanding CO tolerance for alkaline HOR electrocatalysis, attaining 5.7 and 14.3 times mass activity that of p-Rh2P NCs and commercial Pt/C, respectively. This work sheds light on breaking the surface atomic monogeneity for the development of efficient heterogeneous catalysts. 相似文献