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41.
Dr. Nimisha Jain Angelina Mary Tanu Singh Srushti Gadiyaram Dr. Jyoti Joshi Dr. D. Amilan Jose Dr. Abbas Raja Naziruddin 《欧洲无机化学杂志》2023,26(26):e202300210
We report heteroleptic ruthenium complexes of terpyridine (tpy) ligands with directly linked carboxylic acid anchors. These complexes feature methyl or methoxy-substituted 4′−Phtpy as donor ligands. We prepared these heteroleptic complexes from the ruthenium (II) precursor via a milder route to preclude the homoleptic complex formation. The donor−acceptor arrangement of tpy ligands in these ruthenium complexes renders visible light absorption giving metal and ligand-to-ligand charge transfer excitations at c.a. 490 nm. We evaluate the effect of the tpy donor substituents on the light-harvesting ability in Dye-Sensitized Solar Cells (DSSCs) and compare their photosensitizing ability with heteroleptic complexes bearing phenyl spacer at the acceptor end. Further, scrutinizing their photovoltaic performance, we studied their electron transfer kinetics in DSSCs using electrochemical impedance spectroscopy. This paper presents the structure-photosensitization relationship of these heteroleptic ruthenium complexes through a combined experimental and computational approach. 相似文献
42.
The present study describes the simple and fast preparation of Cerium (III) hexacyanoferrate (II) (CeHCF) solid nanoparticles at three different water/formamide (%) ratios used as solvent (v/v) (100:0, 80:20, 0:100). CeHCF nanoparticles (Nps) were characterized by fourier transform infrared pectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), zeta potential and cyclic voltammetry (CV). Electrodes modified with CeHCF presented a well-defined redox pair with formal potential (Eo′) of approximately 0.29 V (vs. Ag/AgCl(sat) attributed to the Fe2 +/Fe3+ redox pair in the presence of cerium (III)). The Nps in the three systems investigates, presents a random size distribution to different surface, where most were distributed between 20 and 160 nm. Considering the three investigated systems, only CeHCF-1 (100:0) was sensitive to L-dopamine, presenting a linear signal region as a function of L-dopamine concentrations, with a limit of detection (LD) of 0.125 mmol L−1, limit of quantification (LQ) of 0.419 mmol L−1 and amperometric sensitivity (S) of 148.16 μA mmol L−1. 相似文献
43.
Zhen Zhu Hsiang-Ning Luk Yi-Min Huang Yu-Cheng Zhang Xu-Jia Chang Ren-Jang Wu 《中国化学会会志》2023,70(4):928-937
This study used a facile method to develop a novel silver/Graphene–polypyrrole (Ag/G–PPy)-modified electrode that can be used as an electrochemical sensor for levosimendan detection. The properties of the synthesized Ag/G–PPy-modified electrode were examined through field-emission scanning electron microscopy, x-ray diffraction, and transmission electron microscopy. The Ag/G–PPy-modified electrode exhibited satisfactory current signals toward levosimendan concentrations ranging from 0.21 to 6.88 μM and exhibited a low detection limit (0.12 μM). Accordingly, the proposed electrode can serve as a simple and inexpensive electrochemical sensor for levosimendan detection. 相似文献
44.
赭曲霉毒素A(Ochratoxin A,OTA)是一种由赭曲霉、青霉菌等真菌产生的次级代谢产物,在自然界分布广泛,具有肝毒性、肾毒性、致癌、致突变作用。鉴于其危害的严重性和污染的广泛性,发展高灵敏度的OTA检测技术引起了研究者的广泛关注。该文阐述了近年来新型电化学传感技术在OTA 检测方面的发展及应用,全面综述了目前OTA电化学传感器的主要类型及其优缺点,并对其发展方向提出了展望,从而为基于OTA的电化学传感器的深入研究与应用提供了参考。 相似文献
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Compared with noble metal platinum (Pt)-based catalysts, inexpensive non-noble metal electrocatalysts have attracted extensive attention for oxygen reduction reaction (ORR). Herein, chitosan as a kind of biomass resource rich in nitrogen and carbon was used to prepare nitrogen-doped carbon (N-C) and N-C in-situ anchored by copper nanoparticles (Cu/N-C). The as-obtained N-C and Cu/N-C nanoparticles were successfully used as non-noble eletrocatalysts tested for ORR. Compared with the N-C, the Cu/N-C showed the high surface area of 607.3 m2窑g-1 with the mean pore size of 2.5 nm and the pore volume of 0.40 cm3窑g-1. The most positive Gibbs free energy change was the rate determining step for ORR process with the 4e mechanism, where the value of the Cu (111)/N-C(-0.39 eV) was lower than that of the N-C(-0.26 eV). The Cu/N-C exhibited superior onset and half-wave potentials (0.96 V and 0.84 V, respectively) in alkaline media (0.1 mol窑L-1 KOH), all of which are much better than those measured for N-C and commercial Pt/C. Furthermore, the Cu/N-C showed superior methanol crossover avoidance and oxygen reduction stability. © 2021 Authors. All rights reserved. 相似文献
48.
在锂-硫化聚丙烯腈电池体系中,负极锂枝晶的形成和生长严重恶化了电池充放电性能,并给电池带来了安全隐患。而在更有利于稳定正极硫化聚丙烯腈材料的碳酸酯类电解液中,锂枝晶生长尤为严重。本文通过将硝酸镁添加到碳酸酯类电解液中,研究硝酸根和镁离子对锂金属表面改性的共同作用。实验数据发现,在硝酸根和镁离子共同作用下,锂枝晶生长被有效抑制。当硝酸镁浓度为100 mmol·L-1时,锂铜半电池的库仑效率明显提高,并显著改善了锂-硫化聚丙烯腈电池的循环性能。300次循环后容量保持率为71%,远高于硝酸锂的61%和无添加剂的50%。 相似文献
49.
与贵金属铂基电化学氧还原反应(ORR)催化剂相比,廉价的非贵金属催化剂引起了广泛的关注。本文以壳聚糖作为一种富含氮和碳元素的生物质资源,利用碳浴法成功制备了氮掺杂碳原位负载铜纳米颗粒(Cu/N-C)催化剂。纯壳聚糖碳化得到的样品N-C的比表面积为67.5 m2·g-1、平均孔径0.14 nm、平均孔体积8.00 m2·g-1,与之相比,Cu/N-C比表面积可达607.3 m2·g-1、平均孔径为2.5 nm、平均孔体积为0.40 cm3·g-1。通过密度泛函理论(DFT)进行计算表明,Cu(111)/N-C的自由能值低于N-C,更有利于氧还原催化进行。在0.1 mol·L-1 KOH的介质中,Cu/N-C不仅表现出优异的起始和半波电势(分别为0.96 V和0.84 V),而且还表现出了优异的抗甲醇性能和稳定性,并且Cu元素掺杂量达到1.67wt.%。 相似文献
50.
Hui Xie Yanyan Niu Ying Deng Hui Cheng Chengxiang Ruan Guangjiu Li Wei Sun 《中国化学会会志》2021,68(1):114-120
In this paper, an electrochemical aptamer sensor was proposed for the highly sensitive detection of mercury ion (Hg2+). Carbon nanofiber (CNF) was prepared by electrospinning and high‐temperature carbonization, which was used for the loading of platinum nanoparticles (PtNPs) by the hydrothermal method. The Pt@CNF nanocomposite was modified on the surface of carbon ionic liquid electrode (CILE) to obtain Pt@CNF/CILE, which was further decorated by gold nanoparticles (AuNPs) through electrodeposition to get Au/Pt@CNF/CILE. Self‐assembling of the thiol‐based aptamer was further realized by the formation of Au‐S bond to get an electrochemical aptamer sensor (Aptamer/Au/Pt@CNF/CILE). Due to the specific binding of aptamer probe to Hg2+ with the formation of T‐Hg2+‐T structure, a highly sensitive quantitative detection of Hg2+ could be achieved by recording the changes of current signal after reacting with Hg2+ within the concentration range from 1.0 × 10?15 mol/L to 1.0 × 10?6 mol/L and the detection limit of 3.33 × 10?16 mol/L (3σ). Real water samples were successfully analyzed by this method. 相似文献