Electrochimica Acta最新文献_第8页

Signal amplification platform based on 2D MOF-on-MOF architectures-derived Co-decorated carbon@nitrogen-doped porous carbon for enhanced electrochemical acetaminophen sensing 基于二维 MOF-on-MOF 架构的信号放大平台，用于增强电化学对乙酰氨基酚传感的 Co-decorated carbon@nitrogen-doped 多孔碳

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-11-01 DOI: 10.1016/j.electacta.2024.145311

Xue Zhang , Xingpai Cai , Tingting Zhang , Zhuzhen Chen , Wangxing Cheng , Zhenbao Li , Linwei Chen , Nannan Lu

Two-dimensional (2D) carbon-carbon hybrids derived from metal-organic frameworks (MOFs) are regarded as an intriguing type of electrode material in electrochemical sensing. In this work, a Co-decorated carbon@nitrogen-doped porous carbon heterostructure (Co/C@NC) was prepared via the simple calcination of 2D ZIF-L(Co)@ZIF-8. In this MOF-on-MOF precursor, the outer ZIF-8 layer not only prevents the collapse of ZIF-L(Co) during calcination but also endows the outer carbon an extended surface area and porous structure for more accessible active sites and a fast mass transfer process. Meanwhile, the formed CoNPs could facilitate the generation of graphitic carbon layers, which enhances electrocatalytic activity and boosted conductivity. Owing to these merits, the Co/C@NC-based sensor displays high electrochemical activity for acetaminophen (APAP) detection with a wide linear range (4 × 10^–7 - 2 × 10^–4 M) and a lower detection limit (8.2 × 10^–8 M). The constructed sensor has been utilized for the analysis of APAP in real samples, yielding acceptable recovery between 96.6% and 104.0%. This work presents an efficient and convenient method for designing MOF-on-MOF-derived 2D carbon-carbon hybrids, which hold a promising prospect in electrochemical analysis.

由金属有机框架（MOFs）衍生的二维（2D）碳-碳杂化物被认为是电化学传感中一种有趣的电极材料。在这项工作中，通过简单煅烧二维 ZIF-L(Co)@ZIF-8，制备了 Co 装饰碳@氮掺杂多孔碳异质结构（Co/C@NC）。在这种 MOF-on-MOF 前驱体中，外层 ZIF-8 不仅能防止 ZIF-L(Co)在煅烧过程中塌陷，还能赋予外层碳以更大的比表面积和多孔结构，以获得更多的活性位点和更快的传质过程。同时，形成的 CoNPs 可促进石墨碳层的生成，从而提高电催化活性和导电性。由于这些优点，基于 Co/C@NC 的传感器在对乙酰氨基酚（APAP）的检测中显示出较高的电化学活性，具有较宽的线性范围（4 × 10-7 - 2 × 10-4 M）和较低的检测限（8.2 × 10-8 M）。所构建的传感器已被用于分析实际样品中的对乙酰氨基酚，回收率在 96.6% 到 104.0% 之间。这项工作为设计由 MOF-on-MOF 衍生的二维碳碳杂化物提供了一种高效便捷的方法，在电化学分析领域具有广阔的前景。

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引用次数: 0

Corrosion properties and mechanisms of friction stir lap welded TiB2/2024 aluminum matrix composite joint 搅拌摩擦搭接焊接 TiB2/2024 铝基复合材料接头的腐蚀性能和机理

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-11-01 DOI: 10.1016/j.electacta.2024.145306

Shuai Chen , Pengliang Niu , Yongxian Huang , Yongbing Li , Xurong Fu , Liming Ke , Fencheng Liu , Fenggang Liu

The corrosion properties and mechanisms of friction stir lap welded (FSLWed) TiB₂/2024 aluminum matrix composite joint immersed in 3.5 wt.% NaCl solution were deeply investigated. Electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) and high resolution TEM (HRTEM) were conducted to characterize the microstructural evolution of various zones across the joint cross-section. The appearance and penetration depth of the etched surfaces were observed by scanning electron microscopy (SEM). The elements on the etched surface were analyzed by EPMA. Results show that the corrosion properties of the 600/200 (rotational speed 600 r/min, travelling speed 200 mm/min) joint are higher than those of the 400/200 joint. It is noted that the corrosion properties of the stir zone (SZ) are higher than those of base material (BM) and heat affected zone (HAZ) based on the open circuit potential (OCP), the corrosion current i_corr, the impedance R_corr and the corroded appearance after immersion corrosion regardless of the welding parameters.

深入研究了浸入 3.5 wt.% NaCl 溶液中的搅拌摩擦搭接焊（FSLWed）TiB2/2024 铝基复合材料接头的腐蚀特性和机理。通过电子反向散射衍射 (EBSD)、透射电子显微镜 (TEM) 和高分辨率 TEM (HRTEM) 分析了接头横截面上不同区域的微观结构演变特征。扫描电子显微镜（SEM）观察了蚀刻表面的外观和渗透深度。用 EPMA 分析了蚀刻表面上的元素。结果表明，600/200（转速 600 r/min，移动速度 200 mm/min）接头的腐蚀性能高于 400/200 接头。根据开路电位 (OCP)、腐蚀电流 icorr、阻抗 Rcorr 以及浸泡腐蚀后的腐蚀外观，可以看出无论焊接参数如何，搅拌区 (SZ) 的腐蚀性能都高于母材 (BM) 和热影响区 (HAZ)。

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引用次数: 0

Hierarchical Co3O4 anode for high-performance Na-ion battery 用于高性能钠离子电池的分层 Co3O4 阳极

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-11-01 DOI: 10.1016/j.electacta.2024.145309

Mewin Vincent , Sandra Sajeev , Monika Srivastava , Ewa Kowalska , Sugarthi Srinivasan , Damian Kowalski

Despite excellent theoretical perditions, sodium-ion batteries have not yet evolved as a reliable replacement of current lithium-ion technology, mostly due to a lack of high capacity-long cycling electrodes. Among the various candidates cobalt(II,III)oxide, Co₃O₄, is expected to deliver an excellent electrochemical characteristics, owing to its multi-electron conversion type nature, however, usually fails in terms of performance due to the electrode inconsistencies, associated with the poor conductivity and volumetric fluctuations. Herein, we report morphology and crystallinity engineering of the Co₃O₄ nanostructure to substantially improve the charge storage as well as cycling performance. Largely interconnected hierarchical Co₃O₄ synthesized via highly reproducible and industrially viable approach demonstrated efficient charge transport kinetics and excellent volume expansion buffering under the de/sodiation cycles. With its unique structural properties hierarchical electrode delivered an excellent reversible capacity (70 % of theoretical limit @25 mAg^-1), rate performance (123 mAhg^-1 @1Ag^-1) and stable cycling (82 % after 250 cycles @1Ag^-1). In-situ Raman analysis of the electrode reactions revealed conversion type Na-ion storage in the hierarchical type of electrodes.

尽管钠离子电池的理论熵值极高，但它尚未发展成为当前锂离子技术的可靠替代品，主要原因是缺乏高容量、长循环电极。在各种候选钴（II,III）氧化物（Co3O4）中，Co3O4 因其多电子转换类型的性质而有望提供出色的电化学特性，但由于电极导电性差和体积波动相关的不一致性，其性能通常不尽如人意。在此，我们报告了 Co3O4 纳米结构的形态和结晶度工程，以大幅提高电荷存储和循环性能。通过高度可重复性和工业可行性的方法合成的大面积相互连接的分层 Co3O4 在脱氧/钠化循环中表现出高效的电荷传输动力学和出色的体积膨胀缓冲能力。凭借其独特的结构特性，纳米片电极具有出色的可逆容量（理论极限的 70% @25 mAg-1）、速率性能（123 mAhg-1 @ 1Ag-1）和稳定的循环性能（250 次循环后的 82% @ 1Ag-1）。对电极反应的原位拉曼分析表明，在分层型电极中存在转化型钠离子存储。

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引用次数: 0

Facile fabrication of N-doped RGO decorated CoS2 nanoparticles as advanced integrated electrode for enhanced supercapacitor performance 轻松制备掺杂 N 的 RGO 装饰 CoS2 纳米粒子，作为先进的集成电极提高超级电容器性能

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-11-01 DOI: 10.1016/j.electacta.2024.145312

Xiaona Li , Weiyang Zhang , Zhengyan Gu , Qingbin Cai , Hongwei Kang , Baocheng Yang , Zhikun Li

Transition metal sulfides (TMSs) are a class of advanced electrode materials for new energy storage devices with superior performance due to their many advantages, such as high specific capacity, good conductivity, low electronegativity, high redox activity, rich variety and low price. Herein, we developed N-doped reduced graphene oxide (N-RGO) decorated CoS₂ nanoparticles nanohybrids (N-RGO/CoS₂, denoted as NGCS) by a facile hydrothermal method. The doped-N process enriches the specific surface area and porosity of RGO nanosheets, which not only forms rich network nanostructures conducive to rapid charge/ion transport, but also promotes more dispersed anchoring of CoS₂, resulting in the formation of smaller-sized CoS₂ nanoparticles that can provide rich and exposed electroactive sites. Therefore, such unique hierarchical porous nanostructures help all components in the nanohybrids to “complement each other's strengths”, so that the fabricated NGCS electrode exhibits a high specific capacitance of 797.1 F g⁻¹ at 0.6 A g⁻¹ and an excellent rate capability with 77.5 % retention (20 A g⁻¹). Furthermore, the assembled NGCS//AC hybrid supercapacitor (HSC) delivers excellent energy density of 41.4 Wh kg⁻¹ (at 719.7 W kg⁻¹) and long-term cyclability with 86.02 % capacitance retention after 13,000 cycles, presenting a promising application potential in new high-performance energy storage and conversion devices.

过渡金属硫化物（TMSs）具有比容量高、导电性好、电负性低、氧化还原活性高、种类丰富、价格低廉等诸多优点，是一类性能优越的新型储能器件用先进电极材料。在此，我们采用简便的水热法开发了掺杂 N 的还原氧化石墨烯（N-RGO）装饰 CoS2 纳米颗粒纳米杂化物（N-RGO/CoS2，简称 NGCS）。掺杂-N过程丰富了RGO纳米片的比表面积和孔隙率，不仅形成了丰富的网络纳米结构，有利于电荷/离子的快速传输，而且促进了CoS2更分散的锚定，从而形成了更小尺寸的CoS2纳米颗粒，可提供丰富的暴露电活性位点。因此，这种独特的分层多孔纳米结构有助于纳米混合体中的所有成分 "优势互补"，从而使制造出的 NGCS 电极在 0.6 A g-1 电流条件下具有 797.1 F g-1 的高比电容和 77.5% 的卓越速率保持能力（20 A g-1）。此外，组装后的 NGCS//AC 混合超级电容器（HSC）具有 41.4 Wh kg-1 的出色能量密度（719.7 W kg-1）和长期循环能力，13,000 次循环后电容保持率为 86.02%，在新型高性能能量存储和转换设备中具有广阔的应用前景。

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引用次数: 0

Corrigendum to “A Single-Ion Transport Interfacial Layer for Solid-State Lithium Batteries” [Electrochimica Acta, Volume 507, 2024, 145181] 固态锂电池的单离子传输界面层"[《Electrochimica Acta》，第 507 卷，2024 年，145181 期] 更正

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-11-01 DOI: 10.1016/j.electacta.2024.145282

Chesta Chesta , Bindu Kalleshappa , Muthu Austeria P , S Sampath

引用次数: 0

The role of hydrogen gas in SRB-induced degradation of X80 pipeline steel in hydrogen-blending environments 氢气在掺氢环境中 SRB 引起的 X80 管道钢降解中的作用

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-11-01 DOI: 10.1016/j.electacta.2024.145301

Zheng Cai , Boxin Wei , Jin Xu , Changkun Yu , Cheng Sun

The pipeline transportation of hydrogen poses higher challenges to the safety of pipes. In this study, the corrosion mechanisms of SRB in X80 pipeline steel under H₂ conditions were investigated. Thermodynamic analysis revealed that the introduction of hydrogen enhances SRB metabolic activity, facilitating the reduction of sulfate to sulfide and promoting hydrogen embrittlement. Additionally, hydrogen permeation tests confirmed that SRB significantly increase hydrogen diffusion in steel, accelerating corrosion. The enhanced hydrogen permeation under biotic conditions was linked to increased hydrogen uptake and sulfide formation, which further destabilized the steel microstructure. This study provides critical insights into the interplay between microbial activity, hydrogen permeation, and corrosion, offering a deeper understanding of the factors influencing hydrogen-assisted corrosion in steel pipelines. The findings contribute to the optimization of material performance and risk assessment in hydrogen-blended environments.

氢气的管道运输对管道安全提出了更高的挑战。本研究对氢气₂条件下 X80 管线钢中 SRB 的腐蚀机理进行了研究。热力学分析表明，氢的引入增强了 SRB 的新陈代谢活动，促进硫酸盐还原成硫化物，促进氢脆。此外，氢渗透试验证实，SRB 显著增加了钢中的氢扩散，加速了腐蚀。在生物条件下，氢渗透的增强与氢吸收的增加和硫化物的形成有关，这进一步破坏了钢微观结构的稳定性。这项研究为微生物活动、氢渗透和腐蚀之间的相互作用提供了重要见解，使人们对影响钢制管道氢辅助腐蚀的因素有了更深入的了解。研究结果有助于优化混合氢环境中的材料性能和风险评估。

引用次数: 0

Natural convection effects in molten LiF-NaF-KF 熔融 LiF-NaF-KF 中的自然对流效应

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-10-31 DOI: 10.1016/j.electacta.2024.145274

Biwu Cai , Jianbang Ge , Zichen Zhang , Yang Gao , Shun Cao , Zhihao Cheng , Xin Lu , Shuqiang Jiao

Understanding mass transfer is of great importance to molten salt electrochemistry. However, natural convection has long been neglected in electrochemical measurements in stagnant molten salt systems due to the complex mathematical treatments. Here we reported the notable natural convection effects in molten LiF-NaF-KF during cyclic voltammetry and chronoamperometry tests. The established model showed that the convection-diffusion layer (CDL) convection dominated mass transfer under long time-scale tests in molten LiF-NaF-KF-EuF₃. However, in the case of molten LiF-NaF-KF-K₂TiF₆, CDL convection predominated at dilute redox concentrations while density-driven convection came into dominance at high redox concentrations, because of the severe coordinate structure change of the redox couple. The derived thickness of the convection-diffusion layer,

δ_{c o n v .}

, ranged from 135 to 183 μm, much higher than that in aqueous solutions (220–250 μm). Moreover, the increase in system temperature greatly enhanced natural convection effects in molten fluorides. Lastly, the use of microelectrode (re<39.7 μm for

δ_{c o n v .}

=160 μm) was demonstrated to be an effective way to suppress the intense natural convection effects.

了解传质对于熔盐电化学非常重要。然而，由于复杂的数学处理，自然对流长期以来在停滞熔盐体系的电化学测量中被忽视。在此，我们报告了熔融 LiF-NaF-KF 在循环伏安法和计时器测试中显著的自然对流效应。已建立的模型显示，在熔融 LiF-NaF-KF-EuF3 的长时间尺度测试中，对流扩散层（CDL）对流主导了传质。然而，在熔融 LiF-NaF-KF-K2TiF6 中，由于氧化还原偶的坐标结构发生了严重变化，CDL 对流在稀氧化还原浓度下占主导地位，而密度驱动对流在高氧化还原浓度下占主导地位。得出的对流扩散层厚度δconv.δconv.在 135 至 183 μm 之间，远高于水溶液中的厚度（220-250 μm）。此外，系统温度的升高大大增强了熔融氟化物的自然对流效应。最后，使用微电极（δconv.δconv.=160 μm 时为 39.7 μm）被证明是抑制强烈自然对流效应的有效方法。

{"title":"Natural convection effects in molten LiF-NaF-KF","authors":"Biwu Cai , Jianbang Ge , Zichen Zhang , Yang Gao , Shun Cao , Zhihao Cheng , Xin Lu , Shuqiang Jiao","doi":"10.1016/j.electacta.2024.145274","DOIUrl":"10.1016/j.electacta.2024.145274","url":null,"abstract":"<div><div>Understanding mass transfer is of great importance to molten salt electrochemistry. However, natural convection has long been neglected in electrochemical measurements in stagnant molten salt systems due to the complex mathematical treatments. Here we reported the notable natural convection effects in molten LiF-NaF-KF during cyclic voltammetry and chronoamperometry tests. The established model showed that the convection-diffusion layer (CDL) convection dominated mass transfer under long time-scale tests in molten LiF-NaF-KF-EuF<sub>3</sub>. However, in the case of molten LiF-NaF-KF-K<sub>2</sub>TiF<sub>6</sub>, CDL convection predominated at dilute redox concentrations while density-driven convection came into dominance at high redox concentrations, because of the severe coordinate structure change of the redox couple. The derived thickness of the convection-diffusion layer, <span><math><msub><mi>δ</mi><mrow><mi>c</mi><mi>o</mi><mi>n</mi><mi>v</mi><mo>.</mo></mrow></msub></math></span>, ranged from 135 to 183 μm, much higher than that in aqueous solutions (220–250 μm). Moreover, the increase in system temperature greatly enhanced natural convection effects in molten fluorides. Lastly, the use of microelectrode (re<39.7 μm for <span><math><msub><mi>δ</mi><mrow><mi>c</mi><mi>o</mi><mi>n</mi><mi>v</mi><mo>.</mo></mrow></msub></math></span>=160 μm) was demonstrated to be an effective way to suppress the intense natural convection effects.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"509 ","pages":"Article 145274"},"PeriodicalIF":5.5,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142555999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fluorine-doped perovskite cathodes with boosted electrocatalytic activity for CO2 electrolysis 提高二氧化碳电解电催化活性的掺氟过氧化物阴极

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-10-31 DOI: 10.1016/j.electacta.2024.145304

Muhammad Nadeem Khan , Lingting Ye , Kui Xie

Global energy demands that have traditionally been satisfied by the use of fossil fuels have led to substantial emissions of CO₂, an important greenhouse gas. Solid oxide electrolysis cells (SOECs) offer a practical approach for transforming CO₂ into valuable fuels. Accordingly, creating stable electrocatalysts and perovskite cathodes capable of efficiently converting CO₂ is a primary aim for the further development of SOECs. Although reconstructing active sites during CO₂ electrolysis is significantly challenging, it is also constrained by our lack of understanding of this process. Herein, we introduce an innovative strategy that involves co-doping with Cu and F to better facilitate the exsolution reaction, which resulted in the formation of an advanced cathode composed of Cu-Fe alloy nanoparticles embedded in a fluorine-doped Sr₂Fe_1.5Mo_0.5O_6−δ (SFM) ceramic matrix. The in-situ electrochemical reconstruction of the SFM cathode through co-doping not only improves mass-transfer efficiency during CO₂ electrolysis but also enhances the catalytic activity and durability of the ceramic cathode. A SOEC assembled with this material as a symmetrical electrode delivered 4.99 mL min⁻¹ cm⁻² of CO at 850 °C and an applied voltage of 1.8 V, which is 168 % higher than that of a pure SFM electrode. In addition, no carbon deposits were observed at the end of the reaction. The co-doping strategy delivered enhanced performance without degradation over 100 h of high-temperature operation, which suggests that it is a reliable cathode material for CO₂ electrolysis. This study introduced an innovative method for improving the SOEC-electrode microstructure and developing efficient electrocatalysts for CO₂ electrolysis.

传统上通过使用化石燃料来满足全球能源需求的做法导致了重要温室气体二氧化碳的大量排放。固体氧化物电解池（SOEC）为将二氧化碳转化为有价值的燃料提供了一种实用方法。因此，创造能够高效转化二氧化碳的稳定电催化剂和过氧化物阴极是进一步开发 SOEC 的首要目标。尽管在二氧化碳电解过程中重建活性位点极具挑战性，但由于我们对这一过程缺乏了解，因此也受到了限制。在本文中，我们介绍了一种创新策略，即通过共同掺杂铜和氟来更好地促进外溶解反应，从而形成一种先进的阴极，该阴极由镶嵌在掺氟 Sr2Fe1.5Mo0.5O6-δ (SFM) 陶瓷基体中的铜铁合金纳米颗粒组成。通过共掺杂对 SFM 阴极进行原位电化学重构，不仅提高了二氧化碳电解过程中的传质效率，还增强了陶瓷阴极的催化活性和耐用性。用这种材料作为对称电极组装的 SOEC 在 850°C 和 1.8 V 的外加电压下可输出 4.99 mL min-1 cm-2 的 CO，比纯 SFM 电极高出 168%。此外，反应结束时未观察到碳沉积。这种共掺杂策略在 100 小时的高温运行过程中未出现性能退化，性能得到了提高，这表明它是一种可靠的二氧化碳电解阴极材料。这项研究为改进 SOEC 阴极微观结构和开发用于二氧化碳电解的高效电催化剂提供了一种创新方法。

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引用次数: 0

Ethanol dimethyl ammonium functionalized poly[ethylene pyrrole/ethylene ketone/propylene ketone] anion exchange membranes for alkaline electrochemical devices 用于碱性电化学设备的乙醇二甲基铵功能化聚[乙烯吡咯/乙烯酮/丙烯酮]阴离子交换膜

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-10-31 DOI: 10.1016/j.electacta.2024.145298

Afaaf Rahat Alvi, Keti Vezzù, Paolo Sgarbossa, Gioele Pagot, Angeloclaudio Nale, Vito Di Noto

This study reports the synthesis of new anion exchange membranes (AEMs) based on poly[N-{N′-(2′-hydroxyethyl)-N′,N′-dimethylammoniumethyl}-ethylenepyrrole(X)/(ethyleneketone)/ (propyleneketone)] (E-FPKK_f(X)_g) with X = I⁻ or OH⁻, obtained by modulating the degree of functionalization (f). The synthesis of these AEMs involves the reaction of poly[ethylene ketone/propylene ketone] with 2-(2-aminoethylamino)ethanol using a Paal-Knorr chemistry. The physical-chemical characteristics of these membranes are extensively analyzed by elemental analysis (CHNS/O), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), high resolution thermogravimetric analysis (HR-TGA) and modulated differential scanning calorimetry (MDSC). The electrical behavior is examined using broadband electric spectroscopy (BES), demonstrating conductivities of 1.66 and 0.084 mS cm⁻¹ 30 °C for the membranes in the hydroxide and iodide form, respectively. Additionally, the stability tests conducted by immersing the membranes in 1 M KOH solution at ambient temperature for 336 h reveal promising chemical resistance in alkaline conditions for the membranes in hydroxide form.

本研究报告了基于聚[N-{N՛-(2՛-羟乙基)-N՛,N՛-二甲基乙基铵}-乙烯吡咯(X)/(乙烯酮)/(丙烯酮)](E-FPKKf(X)g)的新型阴离子交换膜（AEM）的合成，其中 X = I- 或 OH-，可通过调节官能化程度 (f) 而获得。这些 AEM 的合成过程是利用 Paal-Knorr 化学反应法，将聚[乙酮/丙酮]与 2-（2-氨基乙基氨基）乙醇进行反应。通过元素分析（CHNS/O）、衰减全反射傅立叶变换红外光谱（ATR-FTIR）、高分辨率热重分析（HR-TGA）和调制差示扫描量热法（MDSC）对这些膜的物理化学特性进行了广泛分析。使用宽带电光谱（BES）对电学行为进行了检测，结果表明氢氧化物和碘化物形态的膜在 30 °C 时的电导率分别为 1.66 和 0.084 mS cm-1。此外，通过在环境温度下将膜浸入 1 M KOH 溶液中 336 小时进行的稳定性测试表明，氢氧化物形态的膜在碱性条件下具有良好的耐化学腐蚀性。

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引用次数: 0

Unveiling electrochemical insights of lithium manganese oxide cathodes from manganese ore for enhanced lithium-ion battery performance 揭示从锰矿中提取氧化锰锂阴极的电化学原理，提高锂离子电池性能

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2024-10-31 DOI: 10.1016/j.electacta.2024.145286

Mohamed Kerroumi , Mehdi Karbak , Hamza Afaryate , Ayyoub El-Bchiri , Mohamed Aqil , Bouchaib Manoun , Youssef Tamraoui , Hubert Girault , Fouad Ghamouss

Implementing manganese-based electrode materials in lithium-ion batteries (LIBs) faces several challenges due to the low grade of manganese ore, which necessitates multiple purification and transformation steps before acquiring battery-grade electrode materials, increasing costs. At present, most Lithium Manganese Oxide (LMO) materials are synthesized using electrolytic manganese dioxide, and the development of new processes, such as hydrometallurgical processes is important for achieving a cost-effective synthesis of LMO materials. In this work, we develop a full synthesis process of LMO materials from manganese ore, through acid leaching, forming manganese sulfate monohydrate (MnSO₄·H₂O), an optimized thermal decomposition (at 900, 950 or 1000 °C) producing different Mn₃O₄ materials and a solid-state reaction, achieving the synthesis of LMO. The latter was used as a cathode material for LIB exhibiting a specific capacity comparable to the state-of-the-art LMO cathode with a remarkable cycling stability of 800 cycles with <20 % in capacity loss. These performances were attributed to the excellent redox reversibility of the LMO cathode, characterized by voltammetry and in operando and in situ characterization by Raman and XRD.

在锂离子电池（LIB）中使用锰基电极材料面临着一些挑战，因为锰矿石品位低，在获得电池级电极材料之前必须经过多个提纯和转化步骤，从而增加了成本。目前，大多数锂锰氧化物（LMO）材料都是利用电解二氧化锰合成的，而开发新工艺（如湿法冶金工艺）对于实现 LMO 材料的低成本合成非常重要。在这项工作中，我们从锰矿石中开发了一套完整的 LMO 材料合成工艺，通过酸浸出形成一水硫酸锰（MnSO4-H2O），优化热分解（在 900、950 或 1000°C 下）产生不同的 Mn3O4 材料，以及固态反应，实现 LMO 的合成。后者被用作锂离子电池的阴极材料，显示出与最先进的 LMO 阴极相当的比容量和显著的循环稳定性，可循环 800 次，容量损失小于 20%。这些性能归功于 LMO 阴极出色的氧化还原性，并通过伏安法以及拉曼和 XRD 进行了操作和原位表征。

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引用次数: 0