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161.
A novel kind of inorganic-organic hybrid supramolecular hydrogel with excellent anti-biofouling capability was developed. The hydrogel was formed via ionic interaction between the negative-charged sodium polyacrylate (SPA) entwined clay nanosheets (CNS) and positive-charged polyhedral oligomeric silsesquioxane (POSS) core-based generation one (L-Arginine) dendrimer (POSS-R). 相似文献
162.
The Narrowest Band Gap Ever Observed in Molecular Ferroelectrics: Hexane‐1,6‐diammonium Pentaiodobismuth(III) 下载免费PDF全文
Dr. Han‐Yue Zhang Dr. Zhenhong Wei Dr. Peng‐Fei Li Dr. Yuan‐Yuan Tang Dr. Wei‐Qiang Liao Dr. Heng‐Yun Ye Dr. Hu Cai Prof. Ren‐Gen Xiong 《Angewandte Chemie (International ed. in English)》2018,57(2):526-530
Narrow band gaps and excellent ferroelectricity are intrinsically paradoxical in ferroelectrics as the leakage current caused by an increase in the number of thermally excited carriers will lead to a deterioration of ferroelectricity. A new molecular ferroelectric, hexane‐1,6‐diammonium pentaiodobismuth (HDA‐BiI5), was now developed through band gap engineering of organic–inorganic hybrid materials. It features an intrinsic band gap of 1.89 eV, and thus represents the first molecular ferroelectric with a band gap of less than 2.0 eV. Simultaneously, low‐temperature solution processing was successfully applied to fabricate high‐quality ferroelectric thin films based on HDA‐BiI5, for which high‐precision controllable domain flips were realized. Owing to its narrow band gap and excellent ferroelectricity, HDA‐BiI5 can be considered as a milestone in the exploitation of molecular ferroelectrics, with promising applications in high‐density data storage and photovoltaic conversion. 相似文献
163.
Zhichao Cheng Dr. Huifang Shi Dr. Huili Ma Lifang Bian Qi Wu Long Gu Suzhi Cai Xuan Wang Prof. Wei‐wei Xiong Prof. Zhongfu An Prof. Wei Huang 《Angewandte Chemie (International ed. in English)》2018,57(3):678-682
A new type of materials, organic salts in the crystal state, have ultralong organic phosphorescence (UOP) under ambient conditions. The change of cations (NH4+, Na+, or K+) in these phosphors gives access to tunable UOP colors ranging from sky blue to yellow green, along with ultralong emission lifetimes of over 504 ms. Single‐crystal analysis reveals that unique ionic bonding can promote an ordered arrangement of organic salts in crystal state, which then can facilitate molecular aggregation for UOP generation. Additionally, reversible ultralong phosphorescence can be realized through the alternative employment of fuming gases (ammonia and hydrogen chloride), demonstrating its potential as a candidate for visual ammonic or hydrogen chloride gas sensing. The results provide an environmental responsible and practicable synthetic approach to expanding the scope of ultralong organic phosphorescent materials as well as their applications. 相似文献
164.
Xinyu Yang Shuai Yuan Dr. Lanfang Zou Hannah Drake Yingmu Zhang Dr. Junsheng Qin Dr. Ali Alsalme Dr. Hong‐Cai Zhou 《Angewandte Chemie (International ed. in English)》2018,57(15):3927-3932
Epitaxial growth of MOF‐on‐MOF composite is an evolving research topic in the quest for multifunctional materials. In previously reported methods, the core–shell MOFs were synthesized via a stepwise strategy that involved growing the shell‐MOFs on top of the preformed core‐MOFs with matched lattice parameters. However, the inconvenient stepwise synthesis and the strict lattice‐matching requirement have limited the preparation of core–shell MOFs. Herein, we demonstrate that hybrid core–shell MOFs with mismatching lattices can be synthesized under the guidance of nucleation kinetic analysis. A series of MOF composites with mesoporous core and microporous shell were constructed and characterized by optical microscopy, powder X‐ray diffraction, gas sorption measurement, and scanning electron microscopy. Isoreticular expansion of microporous shells and orthogonal modification of the core was realized to produce multifunctional MOF composites, which acted as size selective catalysts for olefin epoxidation with high activity and selectivity. 相似文献
165.
Thioketone‐Directed Palladium(II)‐Catalyzed C−H Arylation of Ferrocenes with Aryl Boronic Acids 下载免费PDF全文
Zhong‐Jian Cai Chen‐Xu Liu Dr. Qing Gu Prof. Dr. Shu‐Li You 《Angewandte Chemie (International ed. in English)》2018,57(5):1296-1299
A palladium(II)‐catalyzed thioketone‐chelation‐assisted direct C?H arylation of ferrocenes is described. With thioketone as an efficient directing group, various monoaryl‐ and diaryl‐substituted thiocarbonylferrocenes were obtained by palladium‐catalyzed direct C?H functionalization in high yields under mild and base‐free reaction conditions. Furthermore, the arylated thiocarbonylferrocene could undergo diverse transformations. 相似文献
166.
Kun Ling Dr. Huili Ma Suzhi Cai Lulu Song Chaoqun Ma Prof. Hai Li Prof. Guichuan Xing Prof. Xiaochun Hang Dr. Jiewei Li Yaru Gao Dr. Wei Yao Prof. Zhigang Shuai Prof. Zhongfu An Prof. Xiaogang Liu Prof. Wei Huang 《Angewandte Chemie (International ed. in English)》2018,57(28):8425-8431
Smart materials with ultralong phosphorescence are rarely investigated and reported. Herein we report on a series of molecules with unique dynamic ultralong organic phosphorescence (UOP) features, enabled by manipulating intermolecular interactions through UV light irradiation. Our experimental data reveal that prolonged irradiation of single‐component organic phosphors of PCzT, BCzT, and FCzT under ambient conditions can activate UOP with emission lifetimes spanning from 1.8 to 1330 ms. These phosphors can also be deactivated back to their original states with short‐lived phosphorescence by UV irradiation for 3 h at room temperature or through thermal treatment. Additionally, the dynamic UOP was applied successfully for a visual anti‐counterfeiting application. These findings may provide unique insight into dynamic molecular motion for optical processing and expand the scope of smart‐response materials for broader applications. 相似文献
167.
Xiao-Tong Zhu Qi Zhao Shi-Da Wang Tian-Shu Zhang Pei-Jun Cai Wen-Juan Hao Shu-Jiang Tu Bo Jiang 《Tetrahedron》2018,74(5):585-593
A new sulfenylation reaction has been established, stereoselectively affording 37 examples of α-arylthio-α,β-unsaturated ketones with generally good yields via a metal-free three-component reaction of α-thiocyanate ketones with diaryliodonium salts and 1,2-dicarbonyls. The reaction enabled multiple bond-forming events including C(sp2)–S formation to provide a high-efficient and practical method toward α-arylthio-α,β-unsaturated ketones. The reasonable mechanism for forming α-arylthio-α,β-unsaturated ketones was proposed. 相似文献
168.
Novel six-membered cyclic phosphate mimics (5-halo-3,3-difluoro-3,6-dihydro-2H-1,2-oxaphosphinine 2-oxides) were synthesized via CuX2 (X?=?Br, Cl)-mediated halocyclization of 1,1-difluoro-2,3-allenylphosphonic acid monoesters in moderate to good yields with high regio-selectivity. This reaction represents the first example of transition metal-mediated intramolecular cyclization of a P-OH moiety to β-allenylphosphonates with a carbon-carbon double bond. 相似文献
169.
Facile,Quick, and Gram‐Scale Synthesis of Ultralong‐Lifetime Room‐Temperature‐Phosphorescent Carbon Dots by Microwave Irradiation 下载免费PDF全文
Kai Jiang Dr. Yuhui Wang Xiaolu Gao Prof. Congzhong Cai Prof. Hengwei Lin 《Angewandte Chemie (International ed. in English)》2018,57(21):6216-6220
Long‐lifetime room‐temperature phosphorescence (RTP) materials are important for many applications, but they are highly challenging materials owing to the spin‐forbidden nature of triplet exciton transitions. Herein, a facile, quick and gram‐scale method for the preparation of ultralong RTP (URTP) carbon dots (CDs) was developed via microwave‐assisted heating of ethanolamine and phosphoric acid aqueous solution. The CDs exhibit the longest RTP lifetime, 1.46 s (more than 10 s to naked eye) for CDs‐based materials to date. The doping of N and P elements is critical for the URTP which is considered to be favored by a n→π* transition facilitating intersystem crossing (ISC) for effectively populating triplet excitons. In addition, possibilities of formation of hydrogen bonds in the interior of the CDs may also play a significant role in producing RTP. Potential applications of the URTP CDs in the fields of anti‐counterfeiting and information protection are proposed and demonstrated. 相似文献
170.
Hydrophobic‐Force‐Driven Removal of Organic Compounds from Water by Reduced Graphene Oxides Generated in Agarose Hydrogels 下载免费PDF全文
Chongling Cheng Dr. Yongqing Cai Dr. Guijian Guan Prof. Leslie Yeo Prof. Dayang Wang 《Angewandte Chemie (International ed. in English)》2018,57(35):11177-11181
Hydrophobic reduced graphene oxides (rGOs) were generated in agarose hydrogel beads (AgarBs) by NaBH4 reduction of graphene oxides (GOs) initially loaded in the AgarBs. The resulting rGO‐loaded AgarBs were able to effectively adsorb organic compounds in water as a result of the attractive hydrophobic force between the rGOs in the AgarBs and the organic compounds dissolved in aqueous media. The adsorption capacity of the rGOs was fairly high even toward reasonably water‐soluble organic compounds such as rhodamine B (321.7 mg g?1) and aspirin (196.4 mg g?1). Yet they exhibited salinity‐enhanced adsorption capacity and preferential adsorption of organic compounds with lower solubility in water. Such peculiar adsorption behavior highlights the exciting possibility for adopting an adsorption strategy, driven by hydrophobic forces, in practical wastewater treatment processes. 相似文献