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51.
52.
聚苯胺对2,5-二巯基-1,3,4-噻二唑氧化还原反应的电化学催化作用的循环伏安研究 总被引:4,自引:0,他引:4
研究了聚苯胺(PAn)膜电极在2,5-二巯基-1,3,4-噻二唑(DMcT)溶液中电化学处理或浸泡后的循环伏安(CV)曲线的变化规律.实验结果表明,PAn膜电极在DMcT溶液中进行电化学处理或浸泡过程可使DMcT进入PAn膜内部与PAn形成复合物.PAn对DMcT的电化学催化作用可能和二者之间形成的电子给体-受体复合物有关.该复合物的电化学氧化还原特性不同于PAn和DMcT,其氧化还原反应速率和可逆性均优于DMcT. 相似文献
53.
In this article, we report on efforts to construct a high sensitive electrochemical sensor with immobilized sandwich‐type DNA borne ferrocene (Fc) head for sequence‐specific DNA detection using ultramicroelectrode and low current voltammetry. Based on the difference in deformability between the bending rigid complementary DNA double helix and its anomalous flexile mismatches, the fully complementary target can be distinguished from mismatched targets including the single‐base mismatched target. Detection limit estimated as the amount of DNA is observed to be 100 fM via low current voltammetry. The method offers great promise of high sensitivity and selectivity simultaneously for effective gene identification. 相似文献
54.
Dr. Zhen-Zhen Shen Dr. Shuang-Yan Lang Rui-Zhi Liu Dr. Chi Zhou Yao-Zu Zhang Prof. Dr. Bing Liu Prof. Dr. Rui Wen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(1):e202316781
Lithium–carbon dioxide (Li–CO2) battery technology presents a promising opportunity for carbon capture and energy storage. Despite tremendous efforts in Li–CO2 batteries, the complex electrode/electrolyte/CO2 triple-phase interfacial processes remain poorly understood, in particular at the nanoscale. Here, using in situ atomic force microscopy and laser confocal microscopy-differential interference contrast microscopy, we directly observed the CO2 conversion processes in Li–CO2 batteries at the nanoscale, and further revealed a laser-tuned reaction pathway based on the real-time observations. During discharge, a bi-component composite, Li2CO3/C, deposits as micron-sized clusters through a 3D progressive growth model, followed by a 3D decomposition pathway during the subsequent recharge. When the cell operates under laser (λ=405 nm) irradiation, densely packed Li2CO3/C flakes deposit rapidly during discharge. Upon the recharge, they predominantly decompose at the interfaces of the flake and electrode, detaching themselves from the electrode and causing irreversible capacity degradation. In situ Raman shows that the laser promotes the formation of poorly soluble intermediates, Li2C2O4, which in turn affects growth/decomposition pathways of Li2CO3/C and the cell performance. Our findings provide mechanistic insights into interfacial evolution in Li–CO2 batteries and the laser-tuned CO2 conversion reactions, which can inspire strategies of monitoring and controlling the multistep and multiphase interfacial reactions in advanced electrochemical devices. 相似文献
55.
56.
Dr. Shi Tang Dr. Zhi Wang Yanzi Xu Huili Ma Dr. Jia Wang Dr. Christian Larsen Prof. Dongfeng Dang Prof. Ergang Wang Prof. Ludvig Edman 《Angewandte Chemie (International ed. in English)》2023,62(23):e202302874
The emission efficiency of organic semiconductors (OSCs) often suffers from aggregation caused quenching (ACQ). An elegant solution is aggregation-induced emission (AIE), which constitutes the design of the OSC so that its morphology inhibits quenching π–π interactions and non-radiative motional deactivation. The light-emitting electrochemical cell (LEC) can be sustainably fabricated, but its function depends on motion of bulky ions in proximity of the OSC. It is therefore questionable whether the AIE morphology can be retained during LEC operation. Here, we synthesize two structurally similar OSCs, which are distinguished by that 1 features ACQ while 2 delivers AIE. Interestingly, we find that the AIE-LEC significantly outperforms the ACQ-LEC. We rationalize our finding by showing that the AIE morphology remains intact during LEC operation, and that it can feature appropriately sized free-volume voids for facile ion transport and suppressed non-radiative excitonic deactivation. 相似文献
57.
陈华莹周舒莹欧洳坊赖婷婷高思静黄智轩周婉如麦婉茵杨剑萍 《分析试验室》2023,(9):1260-1266
适配体功能化DNA纳米结构是构建新型生物传感器的理想材料,为临床诊断、食品安全、环境监测等领域提供了材料基础。本文介绍了核酸适配体在功能化DNA纳米结构中的作用,论述了适配体功能化DNA纳米结构的构建方法,以及其在基于固定化和构象开关的电化学生物传感器的最新应用研究。本文为适配体功能化DNA生物传感器的构建提供了制备方法以及生物传感策略等方面的参考,并展望了以适配体功能化DNA纳米结构为材料的生物传感器的应用前景。 相似文献
58.
Aster Manyazewal Mola Siraye Esubalew Debebe Menbere Leul Mekonnen 《Electroanalysis》2023,35(3):e202200045
Herein, Ag nanoparticles (NPs) modified MoS2 (Ag−MoS2) was applied to the surface of glassy carbon (GC) to produce a robust electrochemical sensor for the detection of thiabendazole, a common antifungal in the post-harvesting of fruits. Cyclic voltammetry studies confirmed thiabendazole exhibited an irreversible, diffusion-controlled process on Ag−MoS2 with a two-fold increase in peak current than the pristine MoS2. A square wave voltammetry was used for the detection of TBZ. The developed sensor exhibited a linear range between 1–10 μM with LOD down to 0.1 μM (S/N>3). Analysis of TBZ in mango and banana matrices gave a recovery of 91.6–100.4 % indicating the suitability of the sensor for food safety monitoring. 相似文献
59.
An electrophoretically mediated microanalysis method for detection of yoctomole (ymol) alkaline phosphatase (ALP) was developed by a combination of on-capillary enzyme-catalyzed reaction and electrochemical detection. In this method, ALP molecules were electrokinetically injected into a capillary of 10 μm i.d. and then electromigrated to the section of the capillary immersed in a warm water bath of 37 °C, where ALP reacted for a certain time with disodium phenyl phosphate as the enzyme substrate. ALP could be measured through determining the electroactive product phenol of the enzyme-catalyzed reaction by using electrochemical detection. The phenol concentration was proportional to the mass of ALP. As a catalyst, ALP was not consumed during the reaction, which provided amplification of signal with prolonged the reaction time. In order to enhance the signal-to-noise ratio, the detection end of the capillary was etched to a horn-shape and a single carbon fiber microcylinder electrode of 6 μm in diameter as the working electrode was inserted into the detection end of the capillary. Under these conditions, the mass of ALP as low as 1.2 × 10−22 mol (72 molecules) or 4.0 × 10−23 mol (24 molecules) could be detected for the on-capillary reaction time of 15 min or 2 h. 相似文献
60.
设计合成了6个带有烷基链的D-π-A型有机光敏染料应用于染料敏化太阳能电池. 发现长链烷基有利于电池开路光电压的提高. 利用脂肪酸共敏化可进一步提高染料分子的敏化效果, 且提高的程度与脂肪酸的链长有重要关系. 相似文献