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Taito Hashimoto Dr. Ryusei Oketani Masaki Nobuoka Prof. Dr. Shu Seki Prof. Dr. Ichiro Hisaki 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202215836
Porous frameworks composed of non-stoichiometrically mixed multicomponent molecules attract much attention from a functional viewpoint. However, their designed preparation and precise structural characterization remain challenging. Herein, we demonstrate that cocrystallization of tetrakis(4-carboxyphenyl)hexahydropyrene and pyrene derivatives ( CP-Hp and CP-Py , respectively) yields non-stoichiometric mixed frameworks through networking via hydrogen bonding. The composition ratio of CP-Hp and CP-Py in the framework was determined by single crystalline X-ray crystallographic analysis, indicating that the mixed frameworks were formed over a wide range of composition ratios. Furthermore, microscopic Raman spectroscopy on the single crystal indicates that the components are not uniformly distributed such as ideal solid solution, but are done gradationally or inhomogeneously. 相似文献
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Basem Moosa Lukman O. Alimi Weibin Lin Aliyah Fakim Prashant M. Bhatt Mohamed Eddaoudi Niveen M. Khashab 《Angewandte Chemie (International ed. in English)》2023,62(46):e202311555
Porous molecular sorbents have excellent selectivity towards hydrocarbon separation with energy saving techniques. However, to realize commercialization, molecular sieving processes should be faster and more efficient compared to extended frameworks. In this work, we show that utilizing fluorine to improve the hydrophobic profile of leaning pillararenes affords a substantial kinetic selective adsorption of benzene over cyclohexane (20 : 1 for benzene). The crystal structure shows a porous macrocycle that acts as a perfect match for benzene in both the intrinsic and extrinsic cavities with strong interactions in the solid state. The fluorinated leaning pillararene surpasses all reported organic molecular sieves and is comparable to the extended metal–organic frameworks that were previously employed for this separation such as UIO-66. Most importantly, this sieving system outperformed the well-known zeolitic imidazolate frameworks under low pressure, which opens the door to new generations of molecular sieves that can compete with extended frameworks for more sustainable hydrocarbon separation. 相似文献
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Prof. Dr. Dengrong Sun Lok Wing Wong Hok Yin Wong Ka Hei Lai Dr. Lin Ye Xinyao Xv Prof. Dr. Thuc Hue Ly Prof. Dr. Qingming Deng Prof. Dr. Jiong Zhao 《Angewandte Chemie (International ed. in English)》2023,62(4):e202216008
The direct utilization of metal–organic frameworks (MOFs) for electrocatalytic oxygen evolution reaction (OER) has attracted increasing interests. Herein, we employ the low-dose integrated differential phase contrast-scanning transmission electron microscopy (iDPC-STEM) technique to visualize the atomic structure of multivariate MOFs (MTV-MOFs) for guiding the structural design of bulk MOFs for efficient OER. The iDPC-STEM images revealed that incorporating Fe3+ or 2-aminoterephthalate (ATA) into Ni-BDC (BDC: benzenedicarboxylate) can introduce inhomogeneous lattice strain that weaken the coordination bonds, which can be selectively cleaved via a mild heat treatment to simultaneously generate coordinatively unsaturated metal sites, conductive Ni@C and hierarchical porous structure. Thus, excellent OER activity with current densities of 10 and 100 mA cm−2 are achieved over the defective MOFs at small overpotentials of 286 mV and 365 mV, respectively, which is superior to the commercial RuO2 catalyst and most of the bulk MOFs. 相似文献
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Kaofeng Huang Haiyi Qiu Xintong Zhang Wang Luo Ying Chen Jiacheng Zhang Prof. Yihang Chen Prof. Guannan Wang Prof. Kezhi Zheng 《Angewandte Chemie (International ed. in English)》2023,62(14):e202218491
Materials with tunable emission colors has attracted increasing interest in both fundamental research and applications. As a key member of light-emitting materials family, lanthanide doped upconversion nanoparticles (UCNPs) have been intensively demonstrated to emit light in any color upon near-infrared excitation. However, realizing the trichromatic emission in UCNPs with a fixed composition remains a great challenge. Here, without excitation pulsed modulation and three different near-infrared pumping, we report an experimental design to fine-control emission in the full color gamut from core–shell-structured UCNPs by manipulating the energy migration through dual-channel pump scheme. We also demonstrate their potential application in full-color display. These findings may benefit the future development of convenient and versatile optical methos for multicolor tuning and open up the possibility of constructing full-color volumetric display systems with high spatiotemporal resolution. 相似文献
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Dr. Mengyi Xiong Dr. Yuting Wu Dr. Gezhi Kong Whitney Lewis Dr. Zhenglin Yang Hanxiao Zhang Li Xu Ying Liu Qin Liu Prof. Xuhua Zhao Prof. Xiao-Bing Zhang Prof. Yi Lu 《Angewandte Chemie (International ed. in English)》2023,62(37):e202308086
DNA-based probes have gained significant attention as versatile tools for biochemical analysis, benefiting from their programmability and biocompatibility. However, most existing DNA-based probes rely on fluorescence as the signal output, which can be problematic due to issues like autofluorescence and scattering when applied in complex biological materials such as living cells or tissues. Herein, we report the development of bioluminescent nucleic acid (bioLUNA) sensors that offer laser excitation-independent and ratiometric imaging of the target in vivo. The system is based on computational modelling and mutagenesis investigations of a genetic fusion between circular permutated Nano-luciferase (NLuc) and HaloTag, enabling the conjugation of the protein with a DNAzyme. In the presence of Zn2+, the DNAzyme sensor releases the fluorophore-labelled strand, leading to a reduction in bioluminescent resonance energy transfer (BRET) between the luciferase and fluorophore. Consequently, this process induces ratiometric changes in the bioluminescent signal. We demonstrated that this bioLUNA sensor enabled imaging of both exogenous Zn2+ in vivo and endogenous Zn2+ efflux in normal epithelial prostate and prostate tumors. This work expands the DNAzyme sensors to using bioluminescence and thus has enriched the toolbox of nucleic acid sensors for a broad range of biomedical applications. 相似文献
38.
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
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