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91.
结合大分子自组装和分子印迹技术制备了分子印迹聚合物胶束, 并通过电沉积将其固载到电极表面得到分子印迹电化学传感器. 首先以甲基丙烯酸二甲氨基乙酯(DMA)、丙烯酸羟乙酯(HEA)、丙烯酸二异辛酯(EHA)和苯乙烯(St)合成了共聚物poly(DMA-co-HEA-co-EHA-co-St), 在其侧链接枝上双键得到可光交联的双亲共聚物. 以水为沉淀剂诱发该双亲共聚物在含有对乙酰氨基苯酚的溶液中自组装, 得到印迹有对乙酰氨基苯酚的聚合物胶束, 利用动态激光光散射(DLS)和透射电镜(TEM)表征其尺寸和形貌. 最后通过电沉积技术诱导印迹胶束在金电极表面组装, 经紫外光辐照交联后, 洗脱模板分子形成分子印迹膜, 制备了对乙酰氨基苯酚分子印迹传感器, 通过循环伏安法、差分脉冲溶出伏安法研究此印迹传感器的性能. 实验结果表明, 该传感器对对乙酰氨基苯酚具有良好的选择性和灵敏度, 浓度响应线性范围为1×10-6 到4×10-3 mol/L, 检测限为3.3×10-7 mol/L. 相似文献
92.
Jean‐Franois Ayme Sbastien Dhers Jean‐Marie Lehn 《Angewandte Chemie (International ed. in English)》2020,59(30):12484-12492
Three imine‐based metal complexes, having no overlap in terms of their compositions, have been simultaneously generated from the self‐sorting of a constitutional dynamic library (CDL) containing three amines, three aldehydes, and three metal salts. The hierarchical ordering of the stability of the three metal complexes assembled and the leveraging of the antagonistic and agonistic relationships existing between the constituents within the constitutional dynamic network corresponding to the CDL were pivotal in achieving the sorting. Examination of the process by NMR spectroscopy showed that the self‐sorting of the FeII and ZnII complexes depended on an interplay between the thermodynamic driving forces and a kinetic trap involved in their assembly. These results also exemplify the concept of “simplexity”—the fact that the output of a self‐assembling system may be simplified by increasing its initial compositional complexity—as the two complexes could self‐sort only in the presence of the third pair of organic components, those of the CuI complex. 相似文献
93.
Dr. Aaron D. W. Kennedy Ray G. DiNardi Lucy L. Fillbrook Assoc. Prof. William A. Donald Assoc. Prof. Jonathon E. Beves 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(16):e202104461
A photoswitchable ligand and palladium(II) ions form a dynamic mixture of self-assembled metallosupramolecular structures. The photoswitching ligand is an ortho-fluoroazobenzene with appended pyridyl groups. Combining the E-isomer with palladium(II) salts affords a double-walled triangle with composition [Pd3L6]6+ and a distorted tetrahedron [Pd4L8]8+ (1 : 2 ratio at 298 K). Irradiation with 410 nm light generates a photostationary state with approximately 80 % of the E-isomer of the ligand and results in the selective disassembly of the tetrahedron, the more thermodynamically stable structure, and the formation of the triangle, the more kinetically inert product. The triangle is then slowly transformed back into the tetrahedron over 2 days at 333 K. The Z-isomer of the ligand does not form any well-defined structures and has a thermal half-life of 25 days at 298 K. This approach shows how a thermodynamically preferred self-assembled structure can be reversibly pumped to a kinetic trap by small perturbations of the isomer distribution using non-destructive visible light. 相似文献
94.
以正硅酸乙酯(TEOS)和六甲基二硅氮烷(HMDS)为前驱体,研究了引入聚乙烯吡咯烷酮(PVP)对膜层的影响,在碱催化条件下制备了改性的二氧化硅溶胶,并采用提拉涂膜的方法在石英基底上涂膜。对不同组分的薄膜,先经热处理或紫外辐照处理,然后用十八烷基三氯硅烷(OTS)/甲苯溶液对膜层表面进行化学修饰,制备出疏水性能良好的纳米二氧化硅自组装薄膜,分析了不同后处理方法对膜层透过率、接触角、膜层表面微观形貌和激光损伤阈值影响。实验结果表明:溶胶中加入PVP提高了膜层的平整度,经OTS改性后膜层疏水性和激光损伤阈值均得到提高。 相似文献
95.
96.
Yi Xu Siyu Guo Xinjian Mao Jian Feng 《Journal of Dispersion Science and Technology》2018,39(3):443-451
The self-assembly behaviors of a series of zwitterionic heterogemini surfactants CmH2m+1-PO4–(CH2)2-N+(CH3)2-CnH2n+1, abbreviated as Cm-P-N-Cn (m, n?=?9, 9; 9, 12; 9, 15; 9, 18; 12, 12; 12, 15; 12, 18; 15, 15; 15, 18; 18, 18), have been investigated in aqueous solution by the dissipative particle dynamics (DPD) method. Morphologies such as sphere (S), rod (R), planar grid (PG), lamella (L), honeycomb (H), one-, two-, and three-dimensional tunnels (1DT, 2DT, and 3DT) have been observed showing more diversities than those of the corresponding symmetric gemini surfactants Cm-N-N-Cm (m?=?9, 12, 15, 18). With the increase of surfactant concentration in the aqueous solution, a distinct transition path ‘‘S—R—PG—3DT—L—2DT—1DT’’ is proved to be common for all the Cm-P-N-Cn systems. Besides, the hydrophobic chain length has a significant influence on the self-assembly behaviors in the case of m?≠?n. Radial distribution function is an effective method to quantitatively evaluate the interaction and relationship between each functional group in the surfactant molecule and water. Results can provide a new insight into the self-assembly behaviors of zwitterionic heterogemini surfactants and the corresponding applications. 相似文献
97.
Dr. Lei He Prof. Wen-Cui Li Shuang Xu Prof. An-Hui Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(13):3209-3218
Microporous carbons afford high surface areas, large pore volumes, and good conductivity, and are fascinating over a wide range of applications. Traditionally synthesized microporous carbon materials usually suffer from some limitations, such as poor accessibility and slow mass transport of molecules due to the micrometer-scale diffusion pathways and space confinement imposed by small pore sizes. Two-dimensional microporous carbon materials, denoted as microporous carbon nanosheets (MCNs), possess nanoscale thickness, which allows fast mass and heat transport along the z axis; thus overcoming the drawbacks of their bulk counterparts. Herein, recent breakthroughs in the synthetic strategies for MCNs are summarized. Three typical methods are discussed in detail with several examples: pyrolysis of organic precursors with 2D units, a templating method that uses wet chemistry, and the molten salt method. Among them, molecular-based assembly of MCNs in the liquid phase shows more controllable morphology, thickness, and pore size distribution. Finally, challenges in this research area are discussed to inspire future explorations. 相似文献
98.
Jingru Zhai Zhengyu Lei Prof. Kening Sun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(32):7733-7739
To address the problems associated with poor conductivity and large volume variation in practical applications as a conversion cathode, engineering of hierarchical nanostructured FeOF coupled with conductive decoration is highly desired, yet rarely reported. Herein, 3D starfish-like FeOF on reduced graphene oxide sheets (FeOF/rGO) is successfully prepared, for the first time, through a combination of solvothermal reaction, self-assembly, and thermal reduction. Integrating the structural features of the 3D hierarchical nanostructure, which favorably shorten the path for electron/ion transport and alleviate volumetric changes, with those of graphene wrapping, which can further enhance the electrical conductivity and maintain the structural stability of the electrode, the as-prepared FeOF/rGO composite exhibits a superior lithium-storage performance, including a high reversible capacity (424.5 mA h−1 g−1 at 50 mA g−1), excellent stability (0.016 % capacity decay per cycle during 180 cycles), and remarkable rate capability (275.8 mA h−1 g−1 at 2000 mA g−1). 相似文献
99.
Tianyu Shan Liang Gao Xiaoqian Tong Qinqing Du Zhihang An Huiwen He Prof. Jiaping Lin Prof. Si Chen Prof. Xu Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(52):12098-12104
An amazing phenomenon of the relative magnitude of modulus of two liquid-crystal (LC) gels is found inverted under/above their phase transition temperature TLC-iso, which is further proved to be caused by their diverse morphology flexibility. By testing the polarity of two LCs, gelator POSS-G1-Boc (POSS=polyhedral oligomeric silsesquioxane) was discovered to self-assemble into more flexible structures in a relatively low polar LC, whereas more rigid ones are formed in higher polar LC. Hence, a fitting function to connect morphology flexibility with solvent polarity was established, which can even be generalized to a number of common solvents. Experimental observations and coarse-grained molecular dynamics simulations revealed that solvent polarity mirrors a “Morse code”, with each “code” corresponding to a specific morphology flexibility. 相似文献
100.
Bei-Bei Guo Dr. Yue-Jian Lin Prof. Guo-Xin Jin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(41):9721-9727
Four flexible ligands with different lengths, degrees of flexibility, and steric bulk were synthesized and used to prepare metal-directed assemblies. Interestingly, minor differences among the ligands led to products with dramatically different topologies: a binuclear D -shaped macrocycle, tetranuclear rectangles, and hexanuclear trefoil knots. The interconversion of the trefoil-shaped complexes was also investigated. This contribution introduces a rare ligand-controlled trefoil–rectangle shape transformation in solution. 相似文献