Journal of Electroanalytical Chemistry最新文献_第3页

Pomegranate-like cobalt Phosphides@P-Doped carbon Nanostructures with controlled phase as anode materials for Lithium-Ion batteries 作为锂离子电池负极材料的石榴状磷化钴@P-掺杂碳纳米结构的可控相位

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-06 DOI: 10.1016/j.jelechem.2024.118760

Anyu Hu, Qihui Liu, Tao Fang, Yijing Pan, Siyi Huang, Yanpeng Fu, Zhicong Shi

Transition metal phosphides (TMPs) have recently emerged as prominent energy conversion and storage materials owing to their unique physicochemical property. Nevertheless, it’s still a difficult task to obtain phase-control of TMPs owing to multiple energetically favorable stoichiometries. Herein, a phase-controllable cobalt phosphide@C with the pomegranate core–shell structure are successfully realized by employing Co-glycerate as precursors and phytic acid (PA) as P sources, etching and coordination agents. With the presence of six phosphoryl groups and the strong coordination ability, PA allows the self-phosphating of Co atoms and the P-doped carbon shell, as well as the confinement of the obtained nanoparticles Additionally, as an organic acid, PA can etch the Co-glycerate precursors with the formation of hollow structures. With different etching time, metal-rich phosphides Co₂P@C and monophosphides CoP@C are successfully achieved. When applied as anode materials, CoP@C demonstrates superior lithium storage performance by delivering a prominent reversible capacity up to 1187 mAh/g at 0.1 A/g and shows no capacity loss at 1 A/g after 500 cycles. This work presents a simple protocol to obtain TMPs with tunable metal/phosphorus ratios, phase selectivity and interface engineering, which could be applied in the field of energy storage and electrocatalysis.

过渡金属磷化物（TMPs）因其独特的物理化学特性，近来已成为一种重要的能量转换和储存材料。然而，由于存在多种能量上有利的化学计量，要获得过渡金属磷化物的相位控制仍然是一项艰巨的任务。本文以钴-甘油酸酯为前驱体，植酸（PA）为P源、刻蚀剂和配位剂，成功实现了具有石榴核壳结构的可相控磷化钴@C。此外，作为一种有机酸，植酸可以蚀刻钴甘油酯前驱体并形成中空结构。在不同的蚀刻时间下，成功实现了富金属磷化物 Co2P@C 和单磷化物 CoP@C。在用作正极材料时，CoP@C 表现出卓越的锂存储性能，在 0.1 A/g 时可提供高达 1187 mAh/g 的显著可逆容量，并且在 1 A/g 循环 500 次后无容量损失。这项研究提出了一种简单的方法来获得具有可调金属/磷比例、相选择性和界面工程的 TMPs，可应用于储能和电催化领域。

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引用次数: 0

Transition metal-assisted layer-by-layer binder free deposition for high-performance energy storage devices 用于高性能储能设备的过渡金属辅助逐层无粘合剂沉积技术

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-05 DOI: 10.1016/j.jelechem.2024.118766

Muhammad Zahir Iqbal , Ayesha Zakir , Maira Javed , Rashid Ali , Abhinav Kumar , H.H. Hegazy , A.A. Alahmari

The increasing energy demands of the world necessitate the development of advanced energy storage systems. Hybrid supercapacitors (HSCs) have emerged as promising candidates, combining the high specific power density (P_S) of supercapacitors (SCs) with the high specific energy density (E_S) of batteries (BATs). However, its performance is dependent on the properties of electrode materials, which need enhancements in conductivity, surface area, and electrochemical stability. In this study, we utilized magnetron sputtering technique for exploring the potential of interface engineering to improve the electrochemical performance of tungsten disulfide (WS₂) as a battery grade electrode material by incorporating chromium (Cr) and titanium (Ti) as an interfacial layer. This strategic modification significantly increased the conductivity, charge transfer efficiency, and structural stability of the WS₂ electrode. Electrochemical experimentation in both half-cell and full-cell configurations revealed that the WS₂/Cr and WS₂/Ti electrode exhibits superior C_S [2400 and 3800] F/g, respectively compared to pristine WS₂. Fabricated WS₂/Cr//AC and WS₂/Ti//AC attained E_S [95 and 117] Wh/kg and P_S [6800 and 8500] W/kg, respectively. The outcomes from the electrochemical testing further demonstrated the superior cyclic stability of WS₂/Cr//AC and WS₂/Ti//AC with [96.5 and 98.3] % which shows that Cr and Ti as an interfacial layer not only mitigates the limitations of WS₂ but also enables the devices to achieve higher performance metrics, underscoring the critical role of interface engineering in advancing HSCs technologies.

全球能源需求日益增长，因此有必要开发先进的储能系统。混合超级电容器（HSCs）结合了超级电容器（SCs）的高比功率密度（PS）和电池（BATs）的高比能量密度（ES），已成为前景广阔的候选产品。然而，其性能取决于电极材料的特性，电极材料需要增强导电性、表面积和电化学稳定性。在这项研究中，我们利用磁控溅射技术探索了界面工程的潜力，通过加入铬（Cr）和钛（Ti）作为界面层，提高了二硫化钨（WS2）作为电池级电极材料的电化学性能。这种策略性改性大大提高了 WS2 电极的导电性、电荷转移效率和结构稳定性。在半电池和全电池配置下进行的电化学实验表明，与原始 WS2 相比，WS2/Cr 和 WS2/Ti 电极表现出更高的 CS [2400 和 3800] F/g。制备的 WS2/Cr//AC 和 WS2/Ti//AC 分别达到了 ES [95 和 117] Wh/kg 和 PS [6800 和 8500] W/kg。电化学测试的结果进一步表明，WS2/Cr//AC 和 WS2/Ti//AC 的循环稳定性极佳，分别为 [96.5 和 98.3]%，这表明作为界面层的铬和钛不仅能缓解 WS2 的局限性，还能使器件达到更高的性能指标，凸显了界面工程在推动 HSCs 技术发展中的关键作用。

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引用次数: 0

Oxygen vacancy-rich Nd-doped RuO2 for efficient acid overall water splitting 富氧空位掺杂钕的 RuO2 用于高效酸性整体水分离

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-04 DOI: 10.1016/j.jelechem.2024.118756

Boyan Ai, Guoxiang Wang, Pengchao Liang, Jinxiu Bing, Majie Zhang, Qingwang Min, Xinxin Zhang

The development of highly active and acid-stable Ru-based electrocatalysts is of great significance for water electrolysis but remains a huge challenge due to serious Ru corrosion in an acid medium. Herein, we prepared oxygen vacancy (O_V)-rich Nd-doped RuO₂ nanocrystals by facile synthesis via hydrothermal and subsequent annealing for efficient overall water splitting. The catalyst exhibits an overpotential of only 200 mV for OER and 44 mv for HER at the current density of 10 mA cm⁻² in 0.5 M H₂SO₄ electrolyte. Nd-doped RuO₂ only demands a cell voltage of 1.52 V to drive the overall water splitting reaction and displays excellent stability for 100 h. Density functional theory further revealed that the newly constructed Nd-doped RuO₂ sites activate the difficult to react *O intermediates, reducing the adsorption energy of the OER intermediates to effectively minimize the Gibbs free energy (*O to *OOH) of the reaction rate-determining step and regulate the center of the active site d-band. The synergistic effect of aliovalent doping and vacancy engineering contributes to the excellent electrocatalytic performance of Nd-doped RuO₂. This performance control strategy can pave the way for the development of effective and economically viable catalysts.

开发高活性、酸性稳定的 Ru 基电催化剂对电解水具有重要意义，但由于 Ru 在酸性介质中受到严重腐蚀，因此开发 Ru 基电催化剂仍是一项巨大挑战。在此，我们通过水热法合成富含氧空位（OV）的掺钕 RuO2 纳米晶体，并随后进行退火处理，制备出高效的整体水分离催化剂。在 0.5 M H2SO4 电解质中，电流密度为 10 mA cm-2 时，该催化剂的 OER 过电位仅为 200 mV，HER 过电位为 44 mv。密度泛函理论进一步揭示，新构建的掺钕 RuO2 位点激活了难以反应的 *O 中间体，降低了 OER 中间体的吸附能，从而有效降低了反应速率决定步骤的吉布斯自由能（*O 至 *OOH），并调节了活性位点 d 带的中心。异价掺杂和空位工程的协同效应造就了掺钕 RuO2 卓越的电催化性能。这种性能控制策略可为开发有效且经济可行的催化剂铺平道路。

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引用次数: 0

Effect of capillary action and gravitational force on resistive pulse sensing with nanopipettes 毛细作用和重力对纳米吸头电阻式脉冲传感的影响

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-02 DOI: 10.1016/j.jelechem.2024.118764

Elisabetta Tognoni , Barbara Adinolfi , Marco Ballestri , Greta Varchi , Mario Pellegrino

In Resistive Pulse Sensing, nanoparticles dispersed in solution are individually detected and characterized during their translocation through a narrow pore or channel. Electrophoretic force and fluid flow can be precisely adjusted to direct nanoparticles toward the sensing zone. The impact of various factors on nanoparticle translocation dynamics, including solution ionic strength, pH, applied potential difference, and pipette tip geometry, has been extensively investigated. In this work, we focus on the role of pipette filling height, an experimental parameter often overlooked despite its significant impact on the overall pressure gradient and the resulting flow through the pipette tip. We used a solution of NaCl 150 mM plus 0.1 % v/v Triton X-100 at pH 7.2, a pipette with radius of approximately 200 nm and a voltage of ± 200 mV. Our findings reveal that the pipette filling height emerges as the critical factor dictating the translocation direction of negatively charged 160 nm PMMA particles and surpassing the combined effect of electrokinetic forces. Ultimately, our results indicate that considering the pipette filling level could enhance the accurate interpretation of experimental results, offering an additional parameter for fine-tuning nanoparticles dynamics, thus providing a valuable tool to researchers in this field.

在电阻脉冲传感技术中，分散在溶液中的纳米粒子在通过狭窄的孔隙或通道时会被单独检测和表征。电泳力和流体流动可以精确调节，以引导纳米粒子向传感区移动。各种因素（包括溶液离子强度、pH 值、外加电位差和吸头几何形状）对纳米粒子迁移动力学的影响已得到广泛研究。在这项工作中，我们重点研究了移液管填充高度的作用，尽管这一实验参数对整体压力梯度和由此产生的流经移液管尖端的流量有重大影响，但却经常被忽视。我们使用的溶液是 pH 值为 7.2 的 150 mM NaCl 加 0.1 % v/v Triton X-100，移液管半径约为 200 nm，电压为 ± 200 mV。我们的研究结果表明，移液管填充高度是决定带负电的 160 纳米 PMMA 粒子转移方向的关键因素，其作用力超过了电动力学的综合作用力。最终，我们的研究结果表明，考虑移液管填充高度可以提高实验结果的准确性，为微调纳米粒子动力学提供额外的参数，从而为该领域的研究人员提供有价值的工具。

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引用次数: 0

High entropy alloys mediated formation of multi-oxide nanoparticles on carbon fiber cloths and their synergistic effects in electrochemical performance 高熵合金介导的碳纤维布上多氧化物纳米粒子的形成及其在电化学性能中的协同效应

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-02 DOI: 10.1016/j.jelechem.2024.118762

Yung-Kai Yang, Ching-Hao Liu, Ping-Chun Chen, Hsin-Jung Tsai, Jien-Wei Yeh, Wen-Kuang Hsu

A wet chemistry technique is developed to produce high entropy alloy nanoparticles on carbon fibers. Coatings display solution phase and can be aerially oxygenated into multi-oxides. Electrochemical measurements confirm the generation of high specific capacitance from multi-oxide coatings where individual components show redox reactions at different potentials thus producing large loops of charge–discharge. Comparative study confirms synergistic effects arising from individual oxides in coatings.

开发了一种湿化学技术，用于在碳纤维上生产高熵合金纳米颗粒。涂层显示出溶液相，并可在空气中氧化成多氧化物。电化学测量证实，多氧化物涂层可产生较高的比电容，其中单个成分在不同电位下发生氧化还原反应，从而产生较大的充放电回路。比较研究证实了涂层中单个氧化物产生的协同效应。

引用次数: 0

Zn-phosphate conversion coatings developed on high-strength steels at reduced processing temperature 在加工温度降低的情况下在高强度钢上开发磷酸锌转化涂层

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-01 DOI: 10.1016/j.jelechem.2024.118759

Sheila Silva-Fernández, Belén Díaz, Iria Feijoo, Xosé Ramón Nóvoa, Carmen Pérez

The effect of process time, ultrasonic stirring, and the addition of

H_{2} {PO}_{4}^{-}

on the morphology and corrosion resistance of phosphate conversion coatings was investigated by Scanning Electron Microscopy and electrochemical tests. The phosphating treatments were performed at 50 °C, lower than traditional processes, and pH 2.9 and 2.4. An enhanced film of bigger mass and reduced corrosion rate was produced when the processing time was extended from 6 to 30 min. at pH 2.9. No important changes were identified in the appearance other than a slight crystal coarsening and Zn enrichment. Both the ultrasonic stirring and the addition of

H_{2} {PO}_{4}^{-}

(pH 2.9, 6 min.) accelerate the coating formation rate and assist in the formation of more uniform layers with a greater Zn concentration. An important crystal refinement was also obtained in the ultrasound-induced treatment, whereas no relevant changes were found for the corrosion behaviour. The addition of

H_{2} {PO}_{4}^{-}

in the amount of 10 g/L (pH 2.9, 6 min.) facilitates the formation of a layer with a quality like that found in the longest treatment (30 min.). None of the tested variables provided an effective modification to improve the performance of the conversion layers developed for the baths considered in this study at pH 2.4.

通过扫描电子显微镜和电化学测试研究了工艺时间、超声波搅拌和 H2PO4- 添加量对磷酸盐转化涂层的形貌和耐腐蚀性的影响。磷化处理的温度为 50 °C，低于传统工艺，pH 值为 2.9 和 2.4。当处理时间从 6 分钟延长到 30 分钟，pH 值为 2.9 时，生成的薄膜质量更大，腐蚀速率更低。除了轻微的晶体粗化和锌富集外，没有发现其他重要的外观变化。超声波搅拌和添加 H2PO4-（pH 值为 2.9，6 分钟）都加快了涂层的形成速度，并有助于形成更均匀的镀层和更高的锌浓度。在超声波诱导的处理过程中，晶体也发生了重要的细化，而腐蚀行为却没有发生相关的变化。加入 10 克/升的 H2PO4-（pH 值为 2.9，6 分钟）有助于形成与最长处理时间（30 分钟）相同质量的层。在 pH 值为 2.4 的条件下，所测试的变量都不能有效改善浴液转化层的性能。

{"title":"Zn-phosphate conversion coatings developed on high-strength steels at reduced processing temperature","authors":"Sheila Silva-Fernández, Belén Díaz, Iria Feijoo, Xosé Ramón Nóvoa, Carmen Pérez","doi":"10.1016/j.jelechem.2024.118759","DOIUrl":"10.1016/j.jelechem.2024.118759","url":null,"abstract":"<div><div>The effect of process time, ultrasonic stirring, and the addition of <span><math><mrow><msub><mi>H</mi><mn>2</mn></msub><msubsup><mrow><mi>PO</mi></mrow><mrow><mn>4</mn></mrow><mo>-</mo></msubsup></mrow></math></span> on the morphology and corrosion resistance of phosphate conversion coatings was investigated by Scanning Electron Microscopy and electrochemical tests. The phosphating treatments were performed at 50 °C, lower than traditional processes, and pH 2.9 and 2.4. An enhanced film of bigger mass and reduced corrosion rate was produced when the processing time was extended from 6 to 30 min. at pH 2.9. No important changes were identified in the appearance other than a slight crystal coarsening and Zn enrichment. Both the ultrasonic stirring and the addition of <span><math><mrow><msub><mi>H</mi><mn>2</mn></msub><msubsup><mrow><mi>PO</mi></mrow><mrow><mn>4</mn></mrow><mo>-</mo></msubsup></mrow></math></span> (pH 2.9, 6 min.) accelerate the coating formation rate and assist in the formation of more uniform layers with a greater Zn concentration. An important crystal refinement was also obtained in the ultrasound-induced treatment, whereas no relevant changes were found for the corrosion behaviour. The addition of <span><math><mrow><msub><mi>H</mi><mn>2</mn></msub><msubsup><mrow><mi>PO</mi></mrow><mrow><mn>4</mn></mrow><mo>-</mo></msubsup></mrow></math></span> in the amount of 10 g/L (pH 2.9, 6 min.) facilitates the formation of a layer with a quality like that found in the longest treatment (30 min.). None of the tested variables provided an effective modification to improve the performance of the conversion layers developed for the baths considered in this study at pH 2.4.</div></div>","PeriodicalId":355,"journal":{"name":"Journal of Electroanalytical Chemistry","volume":"975 ","pages":"Article 118759"},"PeriodicalIF":4.1,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142655330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Self-supported FeCo2O4/CoO@CNTs film as cathode material to construct high energy density supercapacitor 以自支撑 FeCo2O4/CoO@CNTs 薄膜为阴极材料构建高能量密度超级电容器

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-01 DOI: 10.1016/j.jelechem.2024.118758

Lei Yuan , Dongkun Fan , Yuanzhen Liu , Zhaohui Li , Chunming Xu , Na Xin

A simple hydrothermal method was used to synthesize FeCo₂O₄/CoO@CNTs composite material as the cathode material of asymmetric supercapacitor. Based on the advantages of single/bimetal oxide and the synergistic effect after compounding, the hierarchical structure material can improve the energy density. The electrode material has a capacitance of 965 F g⁻¹ at 1 A/g. The specific capacitance of an asymmetric supercapacitor assembled with FeCo₂O₄/CoO@CNTs as the positive electrode, carbon nanotubes (CNTs) as the negative electrode and KOH as the electrolyte is 142.5 F g⁻¹ at 1 A/g. The capacity retention rate is 93.7 % after 10,000 cycles, and the device delivered efficient energy of 44.5 Wh kg⁻¹ at 750 W kg⁻¹. It demonstrates the application prospects of the prepared composite materials in energy storage.

采用简单的水热法合成了FeCo2O4/CoO@CNTs复合材料，作为不对称超级电容器的阴极材料。基于单一/双金属氧化物的优点和复合后的协同效应，该分层结构材料可提高能量密度。该电极材料在 1 A/g 时的电容为 965 F g-1。以 FeCo2O4/CoO@CNTs 为正极、碳纳米管（CNTs）为负极、KOH 为电解质组装的不对称超级电容器在 1 A/g 时的比电容为 142.5 F g-1。经过 10,000 次循环后，容量保持率为 93.7%，该装置在 750 W kg-1 的条件下可提供 44.5 Wh kg-1 的有效能量。这表明所制备的复合材料在储能领域具有广阔的应用前景。

引用次数: 0

Tracking the electrocatalytic activity of Au@Ag core–shell nanoparticles for nitrite oxidation via single-entity electrochemistry 通过单实体电化学追踪 Au@Ag 核壳纳米粒子氧化亚硝酸盐的电催化活性

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-01 DOI: 10.1016/j.jelechem.2024.118757

Gowrisankar Aruchamy, Byung-Kwon Kim

Single-entity electrochemistry (SEE) has been extensively utilized for analyzing various substances, elucidating their mechanisms, and predicting particle behavior on electrode surfaces. In this paper, we propose a novel method for analyzing the electrochemical reactions between core–shell nanoparticles (NPs) and nitrite ions at the single-particle level. This method employs single Au@Ag core–shell NPs, nitrite ions (

{NO}_{2}^{-}

), and a carbon ultramicroelectrode (C-UME), utilizing the electrochemical oxidation of

{NO}_{2}^{-}

ions upon collision with individual core–shell nanoparticles on the C-UME surface. Au@Ag core–shell NPs with different ratios were synthesized to achieve the effective oxidation of

{NO}_{2}^{-}

ions, and their electrochemical properties were analyzed. Various parameters, such as applied potential and

{NO}_{2}^{-}

ion concentration, were adjusted in chronoamperometric experiments to analyze the resulting signals. This study is expected to significantly contribute to the analysis of oxidation/reduction, dispersion, and catalytic properties of various NPs, particularly core–shell NPs.

单实体电化学（SEE）已被广泛用于分析各种物质、阐明其机理以及预测粒子在电极表面的行为。本文提出了一种在单颗粒水平上分析核壳纳米颗粒（NPs）与亚硝酸根离子之间电化学反应的新方法。该方法采用单个 Au@Ag 核壳 NPs、亚硝酸根离子（NO2-）和碳超微电极（C-UME），利用亚硝酸根离子与 C-UME 表面上的单个核壳纳米粒子碰撞后发生的电化学氧化反应。为了实现对 NO2- 离子的有效氧化，合成了不同比例的 Au@Ag 核壳 NPs，并分析了它们的电化学特性。在时变实验中调整了各种参数，如外加电位和 NO2- 离子浓度，以分析产生的信号。该研究有望为分析各种 NPs（尤其是核壳 NPs）的氧化/还原、分散和催化特性做出重要贡献。

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引用次数: 0

Electrochemical behaviour of metal ions in ethaline-based solutions: Impact of electrode material 金属离子在乙醛基溶液中的电化学行为：电极材料的影响

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-11-01 DOI: 10.1016/j.jelechem.2024.118761

Vadim L. Filippov, Alexander V. Rudnev

Deep eutectic solvents (DESs) have become increasingly important in material synthesis, particularly in electrodeposition processes. Ethaline – a DES composed of choline chloride and ethylene glycol – stands out due to its low viscosity compared to other DESs which is favourable for the electrodeposition process. Among the key factors influencing electrodeposition, the substrate material can also play a significant role in the electrochemical behaviour of metal ions and resulting deposit morphology at the early stages of film growth. This study investigates the electrochemical behaviour of various metal ions, including Co(II), Fe(II), Ni(II), In(III), Sn(II), Cu(I), and Cu(II), on four selected substrates (Pt, glassy carbon, Au, and Cu) in dried ethaline-based solutions. The research highlights the impact of different working electrode materials on deposition processes and examines the onset potentials for deposit dissolution, providing insights into predicting galvanic replacement reactions in the DES medium. The formation of the complexes of different composition between metal ions and ethaline components leads to the sequence of equilibrium potentials different from aqueous, non-complex electrolyte solutions. As a remarkable example, we demonstrate the occurrence of galvanic replacement reaction between Ni(II) ions and a more noble Sn substrate in ethaline. The findings underscore the importance of considering both the choice of substrate material and the speciation in ethaline-based DESs.

深共晶溶剂（DES）在材料合成，尤其是电沉积工艺中的作用日益重要。乙酞酸是一种由氯化胆碱和乙二醇组成的 DES，与其他 DES 相比，它的粘度较低，有利于电沉积过程，因此脱颖而出。在影响电沉积的关键因素中，基底材料在薄膜生长的早期阶段对金属离子的电化学行为和由此产生的沉积物形态也起着重要作用。本研究调查了四种选定基底（铂、玻璃碳、金和铜）在干燥的乙醇溶液中的电化学行为，包括 Co(II)、Fe(II)、Ni(II)、In(III)、Sn(II)、Cu(I) 和 Cu(II)。研究强调了不同工作电极材料对沉积过程的影响，并考察了沉积物溶解的起始电位，为预测 DES 介质中的电化学置换反应提供了见解。金属离子和乙碱成分之间形成的不同成分的复合物导致了与水性非复合物电解质溶液不同的平衡电位序列。作为一个显著的例子，我们展示了 Ni（II）离子与乙碱性中更惰性的锡基质之间发生的电化学置换反应。这些发现强调了在基于乙醇的 DES 中同时考虑基质材料的选择和种类的重要性。

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引用次数: 0

Voltammetric detection of chlorogenic acid by Poly(3,4-ethylene-dioxythiophene) electrodes 聚（3,4-乙烯二氧噻吩）电极对绿原酸的伏安检测

IF 4.1 3区化学 Q1 CHEMISTRY, ANALYTICAL

Journal of Electroanalytical Chemistry

Pub Date : 2024-10-29 DOI: 10.1016/j.jelechem.2024.118736

Wei-Li Shih, Lin-Chi Chen

This work aims at developing selective detection of chlorogenic acid (CGA), a critical phenolic acid related to the antioxidant level and taste of coffee, by a pristine poly(3,4-ethylenedioxythiophene) (PEDOT) electrode. The electrochemical oxidation of CGA on two types of PEDOT films, electrodeposited in aqueous (water, aq-PEDOT) and non-aqueous solvents (acetonitrile, ACN-PEDOT), were systematically studied and compared. Aq-PEDOT film showed a linear response for CGA in a range from 1.5 µM to 2.5 mM and a sensitivity of 0.33 mA/cm²⋅mM; ACN-PEDOT film showed a non-linear response with residual CGA. For repeated sensing purposes, we chose aq-PEDOT for the CGA sensor demonstration. Although cross-sensitivity with gallic acid (GA) and caffeic acid (CA) at 0.35 V was observed due to the shared catechol structure, selectivity for CGA determination against vanillin (VAN), guaiacol (GUA), theobromine (THB), theophylline (THP), quinic acid (QA), and caffeine (CAF) was confirmed. The distinct sensing behavior of the PEDOT films was further investigated: aq-PEDOT had a relatively flat surface and obeyed diffusion-controlled kinetics for CGA electro-oxidation. In contrast, ACN-PEDOT had a rougher coral-like morphology and strong adsorption characteristics. The measurements in real coffee samples by aq-PEDOT were also demonstrated with the interference from CA compensated. In brief, this study proves the niches and provides in-depth electrochemical kinetics for voltammetric CGA sensing using the PEDOT films prepared in aqueous and non-aqueous environments.

这项研究旨在开发一种原始聚（3,4-亚乙二氧基噻吩）（PEDOT）电极，用于选择性检测绿原酸（CGA），这是一种与咖啡抗氧化水平和口感有关的重要酚酸。我们系统地研究并比较了在水溶液（水，aq-PEDOT）和非水溶液（乙腈，ACN-PEDOT）中电沉积的两种 PEDOT 薄膜上 CGA 的电化学氧化过程。在 1.5 µM 至 2.5 mM 范围内，水溶液-PEDOT 薄膜对 CGA 呈线性响应，灵敏度为 0.33 mA/cm2⋅mM；而 ACN-PEDOT 薄膜对残留的 CGA 呈非线性响应。出于重复传感的目的，我们选择了 aq-PEDOT 来演示 CGA 传感器。虽然由于共享的儿茶酚结构，在 0.35 V 的电压下与没食子酸（GA）和咖啡酸（CA）出现了交叉敏感性，但我们证实了 CGA 检测对香兰素（VAN）、愈创木酚（GUA）、可可碱（THB）、茶碱（THP）、奎宁酸（QA）和咖啡因（CAF）的选择性。我们进一步研究了 PEDOT 薄膜的不同传感行为：Aq-PEDOT 具有相对平坦的表面，在 CGA 电氧化过程中服从扩散控制动力学。相比之下，ACN-PEDOT 具有更粗糙的珊瑚状形貌和强大的吸附特性。使用 aq-PEDOT 在真实咖啡样品中进行的测量也证明，CA 的干扰得到了补偿。简而言之，本研究证明了在水和非水环境中使用制备的 PEDOT 薄膜进行伏安法 CGA 传感的优势，并提供了深入的电化学动力学。

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引用次数: 0