Electrochimica Acta最新文献_第10页

Synthesis of porous carbon Na4Fe3(PO4)2P2O7@C by sol-gel method as a high-rate cathode for sodium-ion batteries

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-15 DOI: 10.1016/j.electacta.2025.145871

Yijin Zeng, Quan Lu, Chunlin Li, Aichun Dou, Yu Zhou, Mingru Su, Panpan Zhang, Yunjian Liu

Na₄Fe₃(PO₄)₂P₂O₇@C (NFPP) has attracted widespread attention from researchers due to its excellent structural stability, low cost, and non-toxic nature, making it one of the most promising energy storage materials for the future. The inherently poor electrical conductivity of NFPP, its actual specific capacity (around 100 mAh g⁻¹) is often lower than its theoretical capacity (129 mAh g⁻¹), which has been a key issue of concern for researchers. In this study, we adopted a mixed enhancement approach, where polyvinyl alcohol (PVA) and a carbon source were appropriately combined. The PVA uniformly adhered to the surface, and during high-temperature pyrolysis, its decomposition resulted in the formation of carbon layers with pores, creating a porous carbon framework network. The presence of a porous carbon framework allows for sufficient electrolyte infiltration, significantly increasing the reaction surface area. As a result, we successfully synthesized NFPPx (with some PVA added) material with a porous carbon framework network. The surface of NFPPx was coated by a porous carbon layer, which provides the provision of a rapid conductive network and abundant sodium-ion transport pathways. NFPP2 exhibits excellent electrochemical performance, with an outstanding reversible specific capacity of 118 mAh g⁻¹ at 0.1C, which corresponds to 91.5% of its theoretical capacity. Additionally, NFPP2 demonstrates remarkable long-term cycling stability and excellent rate performance. After 6,000 cycles at 20C, it retains 90.6% of its capacity with a reversible specific capacity of 78 mAh g⁻¹. Even at a high current rate of 40C, NFPP2 achieves a specific capacity of 69 mAh g⁻¹. This simple method of mixing and enhancing materials has significantly advanced the development of sodium-ion batteries, providing a promising pathway for the future production of porous carbon framework materials.

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引用次数: 0

Strategically-designed environment-friendly tin-based electrodes for sustainable supercapatteries with high specific capacity

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-14 DOI: 10.1016/j.electacta.2025.145846

Susmi Anna Thomas , Jayesh Cherusseri , Mohan Reddy Pallavolu , Mohd Afzal , Deepthi N. Rajendran

Tin is a highly recyclable and environment-friendly material, which has a lower carbon footprint. Tin-based materials contribute to a circular economy hence are highly preferred for supercapattery electrodes. Supercapatteries bridge the gap between the conventional supercapacitors and rechargeable batteries. They use one of its electrodes as battery-type electrode where the charge storage mechanism is similar to that of batteries, i.e. diffusion-controlled mechanisms. Battery-type electrode-active materials are attracting the research community as they exhibit excellent charge storage capabilities with high specific capacity and energy density. Herein, we report the synthesis of sustainable nickel (Ni)-doped tin disulfide (SnS₂) with flake-like morphology using a microwave-assisted hydrothermal method and the preparation of environment-friendly Ni-doped SnS₂/polypyrrole nanocomposites for supercapatteries. This is the first-time report on the synthesis of a battery-type electrode-active material by introducing defects and sulfur vacancy via Ni-doping in SnS₂ to achieve the best electrochemical performance. We analysed the supercapattery performance of the Ni-doped SnS₂ by varying the dopant ratio and an increase in concentration of dopant is found to enhance the supercapacitor performance. This may be due to the presence of higher number of defects created by Ni, which act as active-sites for the enhanced charge transfer reactions to occur. The Ni-doped SnS₂ electrode delivers a mass specific capacity of 199.7 C/g whereas the Ni-doped SnS₂/polypyrrole exhibits a comparatively higher mass specific capacity of 522.43 C/g at a scan rate of 10 mV/s in 2 M KOH (aqueous) electrolyte. An asymmetric supercapattery cell fabricated with Ni-doped SnS₂/polypyrrole as positrode and activated carbon as negatrode delivers a maximum mass specific energy density of 51.77 Wh/kg with a corresponding power density of 2500 W/kg at a current density of 2 A/g.

{"title":"Strategically-designed environment-friendly tin-based electrodes for sustainable supercapatteries with high specific capacity","authors":"Susmi Anna Thomas , Jayesh Cherusseri , Mohan Reddy Pallavolu , Mohd Afzal , Deepthi N. Rajendran","doi":"10.1016/j.electacta.2025.145846","DOIUrl":"10.1016/j.electacta.2025.145846","url":null,"abstract":"<div><div>Tin is a highly recyclable and environment-friendly material, which has a lower carbon footprint. Tin-based materials contribute to a circular economy hence are highly preferred for supercapattery electrodes. Supercapatteries bridge the gap between the conventional supercapacitors and rechargeable batteries. They use one of its electrodes as battery-type electrode where the charge storage mechanism is similar to that of batteries, i.e. diffusion-controlled mechanisms. Battery-type electrode-active materials are attracting the research community as they exhibit excellent charge storage capabilities with high specific capacity and energy density. Herein, we report the synthesis of sustainable nickel (Ni)-doped tin disulfide (SnS<sub>2</sub>) with flake-like morphology using a microwave-assisted hydrothermal method and the preparation of environment-friendly Ni-doped SnS<sub>2</sub>/polypyrrole nanocomposites for supercapatteries. This is the first-time report on the synthesis of a battery-type electrode-active material by introducing defects and sulfur vacancy via Ni-doping in SnS<sub>2</sub> to achieve the best electrochemical performance. We analysed the supercapattery performance of the Ni-doped SnS<sub>2</sub> by varying the dopant ratio and an increase in concentration of dopant is found to enhance the supercapacitor performance. This may be due to the presence of higher number of defects created by Ni, which act as active-sites for the enhanced charge transfer reactions to occur. The Ni-doped SnS<sub>2</sub> electrode delivers a mass specific capacity of 199.7 C/g whereas the Ni-doped SnS<sub>2</sub>/polypyrrole exhibits a comparatively higher mass specific capacity of 522.43 C/g at a scan rate of 10 mV/s in 2 M KOH (aqueous) electrolyte. An asymmetric supercapattery cell fabricated with Ni-doped SnS<sub>2</sub>/polypyrrole as positrode and activated carbon as negatrode delivers a maximum mass specific energy density of 51.77 Wh/kg with a corresponding power density of 2500 W/kg at a current density of 2 A/g.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"522 ","pages":"Article 145846"},"PeriodicalIF":5.5,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143418252","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

Investigating the impact of functionalized graphene oxide on the properties and performance of Poly(2,6-Dimethyl-1,4-Phenylene Oxide)-based anion exchange membranes for fuel cells 研究功能化氧化石墨烯对燃料电池用聚（2,6-二甲基-1,4-苯基氧化物）阴离子交换膜的性质和性能的影响

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-13 DOI: 10.1016/j.electacta.2025.145868

Manoj Karakoti , Kwang Seop Im , Hak Su Jang , Jun Ho Park , Dong Jun Lee , Hyun Woong Kwon , Sang Yong Nam

For the first time, we report on the functionalization of graphene oxide (GO) with 4,4′-methylenedianiline (MDA) and its subsequent quaternization with glycidyltrimethylammonium chloride (GTMAC) to produce quaternized GO (QGO). The synthesized QGO is used as a filler in quaternized poly(2,6-dimethyl-1,4-phenylene oxide) (QPPO) matrix to fabricate an anion exchange membrane for a fuel cell. The QPPO-QGO-0.5% membrane exhibits the highest ion exchange capacity (IEC) and hydroxide ion conductivity (HIC) of 3.10 meq/g and 139 mS/cm, respectively. Additionally, it maintains the 93 % of alkaline stability after 1000 hrs, which is higher than that of pure QPPO and other QGO-mixed QPPO membranes. Furthermore, single H₂/O₂ fuel cell is fabricated using the QPPO-QGO-0.5 % composite membrane, which exhibits the maximum peak power density (MPPD) of 372 mW/cm² at 0.54 V and a current density of 688 mA/cm² which is also higher than the pure QPPO of 311 mW/cm². These results indicate an enhanced performance of fabricated composite membranes as an anion exchange membrane (AEM) for fuel cells, demonstrating their potential for future applications.

我们首次报道了用 4,4'-亚甲基二苯胺（MDA）对氧化石墨烯（GO）进行功能化，然后用缩水甘油基三甲基氯化铵（GTMAC）对其进行季铵化，从而制备出季铵化 GO（QGO）。合成的 QGO 用作季铵化聚（2,6-二甲基-1,4-苯基氧化物）（QPPO）基质的填料，用于制造燃料电池的阴离子交换膜。QPPO-QGO-0.5% 膜具有最高的离子交换容量（IEC）和氢氧根离子导电率（HIC），分别为 3.10 meq/g 和 139 mS/cm。此外，它在 1000 小时后仍能保持 93% 的碱性稳定性，高于纯 QPPO 和其他混合 QGO 的 QPPO 膜。此外，使用 QPPO-QGO-0.5% 复合膜制造的单个 H2/O2 燃料电池在 0.54 V 电压下的最大峰值功率密度 (MPPD) 为 372 mW/cm2，电流密度为 688 mA/cm2，也高于纯 QPPO 的 311 mW/cm2。这些结果表明，制作的复合膜作为燃料电池的阴离子交换膜（AEM）具有更高的性能，显示了其未来的应用潜力。

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引用次数: 0

Two-dimensional MXene based anodic slurry electrodes for vanadium redox flow batteries

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-13 DOI: 10.1016/j.electacta.2025.145865

Ali Vala Mizrak , Huseyin Engin Sever , Jonathan C. Ehring , Kyle Matthews , Iryna Roslyk , Alex Inman , Emin Caglan Kumbur

Vanadium redox flow batteries (VRFBs) are a promising energy storage technology with potential toward supporting the transition to green energy. However, optimizing electrode materials to improve battery performance remains a challenge. Slurry electrodes have recently gained attention for their advantages over conventional carbonaceous electrodes but require further investigation for effective utilization in flow battery systems. To address these issues, we investigated two-dimensional (2D) Ti₃C₂T_x MXene slurry electrodes in VRFBs. We evaluated different concentrations (0.25, 0.5, and 1.0 wt.%) of MXene-based anodic slurry electrodes through comprehensive flow battery tests, including polarization, charge-discharge cycling, and electrochemical impedance spectroscopy. Rheological and hydrodynamic measurements were also conducted to analyze the physical properties of the slurry electrodes. Our findings reveal a 70 % higher voltage and 46 % increase in depth of discharge with the addition of 0.5 wt.% MXene slurry (MX_0.5) compared to the baseline graphite particle suspension electrode. Additionally, MX_0.5 exhibited enhanced rheological and hydrodynamic properties, leading to improved flow characteristics and a significant reduction in pressure drop within the battery system. The enhanced performance of Ti₃C₂T_x was attributed to its unique 2D structure, high surface area, and specific surface chemistry, which collectively enhanced the electrochemical properties of the slurry electrodes.

{"title":"Two-dimensional MXene based anodic slurry electrodes for vanadium redox flow batteries","authors":"Ali Vala Mizrak , Huseyin Engin Sever , Jonathan C. Ehring , Kyle Matthews , Iryna Roslyk , Alex Inman , Emin Caglan Kumbur","doi":"10.1016/j.electacta.2025.145865","DOIUrl":"10.1016/j.electacta.2025.145865","url":null,"abstract":"<div><div>Vanadium redox flow batteries (VRFBs) are a promising energy storage technology with potential toward supporting the transition to green energy. However, optimizing electrode materials to improve battery performance remains a challenge. Slurry electrodes have recently gained attention for their advantages over conventional carbonaceous electrodes but require further investigation for effective utilization in flow battery systems. To address these issues, we investigated two-dimensional (2D) Ti<sub>3</sub>C<sub>2</sub>T<em><sub>x</sub></em> MXene slurry electrodes in VRFBs. We evaluated different concentrations (0.25, 0.5, and 1.0 wt.%) of MXene-based anodic slurry electrodes through comprehensive flow battery tests, including polarization, charge-discharge cycling, and electrochemical impedance spectroscopy. Rheological and hydrodynamic measurements were also conducted to analyze the physical properties of the slurry electrodes. Our findings reveal a 70 % higher voltage and 46 % increase in depth of discharge with the addition of 0.5 wt.% MXene slurry (MX_0.5) compared to the baseline graphite particle suspension electrode. Additionally, MX_0.5 exhibited enhanced rheological and hydrodynamic properties, leading to improved flow characteristics and a significant reduction in pressure drop within the battery system. The enhanced performance of Ti<sub>3</sub>C<sub>2</sub>T<em><sub>x</sub></em> was attributed to its unique 2D structure, high surface area, and specific surface chemistry, which collectively enhanced the electrochemical properties of the slurry electrodes.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"520 ","pages":"Article 145865"},"PeriodicalIF":5.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401345","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

Nitrogen-doped hierarchical porous carbon derived from CO2 for the high-performance cathode of lithium-sulfur battery

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-13 DOI: 10.1016/j.electacta.2025.145867

Dayeon Lee, Jeongwoo Yang, Won Chan Yun, Jae W. Lee

This study presents a novel approach to enhance lithium-sulfur batteries by utilizing nitrogen-doped porous carbon (CPCN) derived from CO₂. CPCN was synthesized from the reaction of carbon dioxide (CO₂) and sodium borohydride (NaBH₄) in the presence of CaCO₃ as a nanotemplate followed by bubbling an ammonia solution. The ammonia solution treatment introduced nitrogen atoms into the carbon structure and increased the material's porosity, thereby providing pathways for more effective lithium-ion diffusion. This treatment also generated various nitrogen functional groups, including pyridinic N, which played a key role in facilitating lithium polysulfide conversion. The surface pyridinic functional groups on CPCN significantly improved its electrochemical performance through interaction with lithium polysulfides. CPCN demonstrated an exceptional maximum discharge capacity of 1,368 mAh/g, surpassing that of non-templated porous carbon (NPC, 922 mAh/g) and CaCO₃-templated porous carbon (CPC, 1,110 mAh/g), respectively, at 0.2C, with a capacity of 1,007 mAh/g maintained after 200 cycles. It also exhibited superior rate capability with a capacity of 726 mAh/g at 3.0C, and showed maximum areal capacity of 3.38 mAh/cm² at 0.2C for an elevated sulfur content of 5.71 mg/cm². The study underscores the advantages of CO₂-derived porous carbon and nitrogen doping in advancing Li-S batteries, offering a sustainable and high-performance solution for energy storage technologies.

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引用次数: 0

Operation condition dependent degradation effects of Li-rich layered oxide/graphite-SiOx pouch-type batteries: An in-situ and ex-situ analyses

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-13 DOI: 10.1016/j.electacta.2025.145866

Xingge Liu , Yi Qian , Xiaopeng Qi , Qiyu Lan , Jingdong Jiang

The utilization of lithium-ion batteries with Li-rich layered oxide cathodes and graphite-SiO_x anodes can address range anxiety in electric vehicles. Despite their potential, these batteries exhibit rapid capacity fading. At a high cutoff voltage of 4.6 V, anode-related capacity losses become evident after 50 cycles, intensifying post-200 cycles due to substantial lithium plating, which leads to irreversible lithium loss and increased impedance. Degradation of the cathode microstructure exacerbates side reactions with the electrolyte, contributing to the overall capacity decline. In-situ three-electrode analysis reveals these phenomena. At 45 °C, the degradation of anode capacity is intensified. After 200 cycles, anode losses become predominant, causing significant voltage displacement. Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC–MS) indicate that electrolyte decomposition is exacerbated at 45 °C, leading to increased irreversible lithium consumption and elevated battery impedance. This study, focusing on in-situ three-electrode and post-mortem analyses, explores the unique capacity degradation mechanisms in high-energy lithium-ion batteries with Li-rich layered oxide/graphite-SiO_x under conditions of high cutoff voltage and elevated temperatures. The findings provide valuable insights, informing future advancements in battery design strategies to enhance the durability and performance of these batteries for real-world electric vehicle applications.

{"title":"Operation condition dependent degradation effects of Li-rich layered oxide/graphite-SiOx pouch-type batteries: An in-situ and ex-situ analyses","authors":"Xingge Liu , Yi Qian , Xiaopeng Qi , Qiyu Lan , Jingdong Jiang","doi":"10.1016/j.electacta.2025.145866","DOIUrl":"10.1016/j.electacta.2025.145866","url":null,"abstract":"<div><div>The utilization of lithium-ion batteries with Li-rich layered oxide cathodes and graphite-SiO<sub>x</sub> anodes can address range anxiety in electric vehicles. Despite their potential, these batteries exhibit rapid capacity fading. At a high cutoff voltage of 4.6 V, anode-related capacity losses become evident after 50 cycles, intensifying post-200 cycles due to substantial lithium plating, which leads to irreversible lithium loss and increased impedance. Degradation of the cathode microstructure exacerbates side reactions with the electrolyte, contributing to the overall capacity decline. In-situ three-electrode analysis reveals these phenomena. At 45 °C, the degradation of anode capacity is intensified. After 200 cycles, anode losses become predominant, causing significant voltage displacement. Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC–MS) indicate that electrolyte decomposition is exacerbated at 45 °C, leading to increased irreversible lithium consumption and elevated battery impedance. This study, focusing on in-situ three-electrode and post-mortem analyses, explores the unique capacity degradation mechanisms in high-energy lithium-ion batteries with Li-rich layered oxide/graphite-SiO<sub>x</sub> under conditions of high cutoff voltage and elevated temperatures. The findings provide valuable insights, informing future advancements in battery design strategies to enhance the durability and performance of these batteries for real-world electric vehicle applications.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"520 ","pages":"Article 145866"},"PeriodicalIF":5.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401347","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

Advanced electrocatalyst for OER by laser treatment of BaCo-oxide powders

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-13 DOI: 10.1016/j.electacta.2025.145864

A. Semenova , S.M. Fink , E. Zykova , Byoung Gun Han , Hyeonseo Jang , Yejin Kim , Deok-Yong Cho , I. Valov

Hydrogen as energy carrier and essential element for production of basic industrial chemicals and substances stays in the focus of the current fundamental and applied research. The most reliable, and at the same time environmentally friendly way for its production is the electrochemical water splitting, and particularly the alkaline water electrolysis. One of the major challenges for industrial implementation of this process is the still high energy losses and related production costs. To solve this issue, finding cheaper and more efficient catalytic materials which are able to operate under industrial conditions is an essential requirement. In this work, we present a laser based sintering processing and analyze the performance of perovskite electrocatalytic material BaCoO_3-δ:Ti / CoO_xfor the oxygen evolution reaction, operating at 73 °C and 1 M KOH. A two-step formation route was used for the powder synthesis and the influence of a Nd:YAG (1064 nm) laser sintering process on the catalyst performance and stability was examined. The effect of power and scanning velocity of the laser sintering of catalyst structure and surface condition was studied. The evaluation of End of Service Life Test was carried out along with tracking structural and chemical changes in the oxide system, revealing Co³⁺/Co⁴⁺-containing phase composition stability. Chemical step (adsorption of *OOH) was found to be rate determining of OER in this catalytic system. The material exhibits a high lifetime, achieving <0.430 mA / cm² h, (current density decrease per hour) degradation rate, evidencing the advantages of the laser treated BCT/CO as efficient material for a long-term OER at industrial relevant conditions.

{"title":"Advanced electrocatalyst for OER by laser treatment of BaCo-oxide powders","authors":"A. Semenova , S.M. Fink , E. Zykova , Byoung Gun Han , Hyeonseo Jang , Yejin Kim , Deok-Yong Cho , I. Valov","doi":"10.1016/j.electacta.2025.145864","DOIUrl":"10.1016/j.electacta.2025.145864","url":null,"abstract":"<div><div>Hydrogen as energy carrier and essential element for production of basic industrial chemicals and substances stays in the focus of the current fundamental and applied research. The most reliable, and at the same time environmentally friendly way for its production is the electrochemical water splitting, and particularly the alkaline water electrolysis. One of the major challenges for industrial implementation of this process is the still high energy losses and related production costs. To solve this issue, finding cheaper and more efficient catalytic materials which are able to operate under industrial conditions is an essential requirement. In this work, we present a laser based sintering processing and analyze the performance of perovskite electrocatalytic material BaCoO<sub>3-δ</sub>:Ti / CoO<sub>x</sub>for the oxygen evolution reaction, operating at 73 °C and 1 M KOH. A two-step formation route was used for the powder synthesis and the influence of a Nd:YAG (1064 nm) laser sintering process on the catalyst performance and stability was examined. The effect of power and scanning velocity of the laser sintering of catalyst structure and surface condition was studied. The evaluation of End of Service Life Test was carried out along with tracking structural and chemical changes in the oxide system, revealing Co<sup>3+</sup>/Co<sup>4+</sup>-containing phase composition stability. Chemical step (adsorption of *OOH) was found to be rate determining of OER in this catalytic system. The material exhibits a high lifetime, achieving <0.430 mA / cm<sup>2</sup> h, (current density decrease per hour) degradation rate, evidencing the advantages of the laser treated BCT/CO as efficient material for a long-term OER at industrial relevant conditions.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"520 ","pages":"Article 145864"},"PeriodicalIF":5.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401346","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

Lithium-induced defect centers in nanorod-shaped zinc oxide for supercapacitor applications

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-13 DOI: 10.1016/j.electacta.2025.145806

Ameen Uddin Ammar , Mohamad Hasan Aleinawi , Maria Stefan , Ahmet Gungor , Adriana Popa , Dana Toloman , Karlo Maškarić , Eminenur Saritas , Lucian Barbu-Tudoran , Sergiu Macavei , Marin Senila , Emre Erdem , Arpad Mihai Rostas

Lithium (Li) doped ZnO nanorods were synthesized in this work using the hydrothermal method by varying the Li ions concentration. The synthesized material was used as an electrode material for supercapacitor application, and the effect of the Li ions on the electrochemical properties was reported. The Li-doped ZnO nanorods were characterized using X-ray diffraction, electron microscopy, and Raman spectroscopy to obtain information on the structural and morphological environment. Electron paramagnetic resonance, Raman, and photoluminescence spectroscopy gave information on the defect environment of the materials, which plays a vital role in this work as a change in the defect structure directly influences the electrochemical properties. Finally, the electrochemical performance of the electrode materials was tested by assembling all-in-one supercapacitor devices using cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic cycling with potential limitations as testing techniques. The result obtained showed extremely positive trends for this type of electrode material. The maximum specific capacitance was achieved for the 0.5% Li-doped ZnO, which showed a value of 700 F/g at 1 mV/s with an impressive energy density of 56 Wh/kg and excellent cyclic stability.

{"title":"Lithium-induced defect centers in nanorod-shaped zinc oxide for supercapacitor applications","authors":"Ameen Uddin Ammar , Mohamad Hasan Aleinawi , Maria Stefan , Ahmet Gungor , Adriana Popa , Dana Toloman , Karlo Maškarić , Eminenur Saritas , Lucian Barbu-Tudoran , Sergiu Macavei , Marin Senila , Emre Erdem , Arpad Mihai Rostas","doi":"10.1016/j.electacta.2025.145806","DOIUrl":"10.1016/j.electacta.2025.145806","url":null,"abstract":"<div><div>Lithium (Li) doped ZnO nanorods were synthesized in this work using the hydrothermal method by varying the Li ions concentration. The synthesized material was used as an electrode material for supercapacitor application, and the effect of the Li ions on the electrochemical properties was reported. The Li-doped ZnO nanorods were characterized using X-ray diffraction, electron microscopy, and Raman spectroscopy to obtain information on the structural and morphological environment. Electron paramagnetic resonance, Raman, and photoluminescence spectroscopy gave information on the defect environment of the materials, which plays a vital role in this work as a change in the defect structure directly influences the electrochemical properties. Finally, the electrochemical performance of the electrode materials was tested by assembling all-in-one supercapacitor devices using cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic cycling with potential limitations as testing techniques. The result obtained showed extremely positive trends for this type of electrode material. The maximum specific capacitance was achieved for the 0.5% Li-doped ZnO, which showed a value of 700 F/g at 1 mV/s with an impressive energy density of 56 Wh/kg and excellent cyclic stability.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"519 ","pages":"Article 145806"},"PeriodicalIF":5.5,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401344","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

Electrochemical decarboxylative oxidation of carboxylic acid mixtures on boron doped diamond electrodes

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-13 DOI: 10.1016/j.electacta.2025.145826

Talal Ashraf , Bastian Timo Mei , Guido Mul

Electrochemical decarboxylation of carboxylic acids is of emerging interest for upgrading of pyrolysis oil. In this study, electrooxidation of propionic acid using BDD electrodes in batch mode is shown to form ethanol and ethylene. The influence of process conditions is elaborated on, and we generally demonstrate that the oxidation of propionic acid on BDD is largely induced by solution based hydroxyl radical chemistry. A high relative ethanol over ethylene Faradaic Efficiency (FE_{ethanol/ethylene}) can be achieved at low current density (25 mA/cm²) and an electrolyte pH of 5, while the FE_{ethanol/ethylene} is affected by consecutive oxidation of ethanol to acetaldehyde and/or CO₂. This is further corroborated by investigating the specificity of BDD in electrooxidation of short chain carboxylic acid mixtures. It is shown that the oxidation specificity is not solely dependent on the rate constant of Formic, Acetic, and Propionic acid with hydroxy radicals, but that surface mediated reactions are also relevant. Finally, we propose mitigation strategies for consecutive oxidation of ethanol at high current densities (100 mA/cm²), using flow cells and pulsed electrolysis to control the near-surface concentration of hydroxyl radicals. In conclusion, this study provides a comprehensive analysis of decarboxylation reactions using BDD anodes and additionally emphasizes the significance of engineering approaches to achieve substrate specificity, a field that has hitherto remained largely unexplored.

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引用次数: 0

Improving photoelectrochemical performance of SnO2 nanocones through TiOx shell via atomic layer deposition

IF 5.5 3区材料科学 Q1 ELECTROCHEMISTRY

Electrochimica Acta

Pub Date : 2025-02-12 DOI: 10.1016/j.electacta.2025.145854

Magdalena Gurgul , Raul Zazpe , Jhonatan Rodriguez-Pereira , Ludek Hromadko , Jan M. Macak , Leszek Zaraska

Amorphous titanium oxide (TiO_x) has recently garnered significant attention due to its disorder-mediated optical and electrical properties, in contrast to the crystalline TiO₂ polymorphs. This research presents a novel approach for preparing SnO₂/TiO_x heterostructures. Ultrathin amorphous TiO_x coatings of varying thicknesses, realized by Atomic Layer Deposition (ALD) on SnO₂ nanocones, were used to investigate their impact on photoelectrochemical properties of resulting SnO₂/TiO_x heterostructures, as well as to enhance chemical and electrochemical stability of SnO₂ itself. Uncoated SnO₂ nanocones were utilized as reference materials for comparative assessment. SnO₂ nanocones were prepared through a modified low-temperature Chemical Vapor Deposition (CVD) method, followed by an application of TiO_x shell using an optimized ALD process. Morphological and chemical characterization of the SnO₂/TiO_x core-shell heterostructure was conducted using field emission electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) and Raman spectroscopy. The light absorption ability was evaluated using UV–Vis spectroscopy, and the photoelectrochemical properties were assessed using monochromatic light and a solar light simulator. The impact of TiO_x shell thickness on photoelectrochemical properties was meticulously assessed and correlated with changes in charge carrier kinetics, providing an understanding of how variations in TiO_x shell dimensions affect photoelectrochemical properties in SnO₂/TiO_x photoanodes.

无定形氧化钛（TiOx）因其无序介导的光学和电学特性而受到广泛关注，这与晶体二氧化钛多晶体形成鲜明对比。本研究提出了一种制备 SnO2/TiOx 异质结构的新方法。通过原子层沉积（ALD）技术在二氧化锡纳米锥上实现不同厚度的超薄无定形氧化钛涂层，以研究其对二氧化锡/氧化钛异质结构的光电化学特性的影响，并提高二氧化锡本身的化学和电化学稳定性。未涂层的二氧化锡纳米锥被用作比较评估的参考材料。二氧化锡纳米锥是通过改良的低温化学气相沉积（CVD）方法制备的，然后使用优化的 ALD 工艺涂覆 TiOx 壳。利用场发射电子显微镜（FE-SEM）、能量色散光谱（EDS）、X 射线衍射（XRD）、X 射线光电子能谱（XPS）和拉曼光谱对 SnO2/TiOx 核壳异质结构进行了形态和化学表征。利用紫外可见光谱评估了光吸收能力，并利用单色光和太阳光模拟器评估了光电化学特性。对 TiOx 外壳厚度对光电化学特性的影响进行了细致的评估，并将其与电荷载流子动力学的变化联系起来，从而了解了 TiOx 外壳尺寸的变化如何影响 SnO2/TiOx 光阳极的光电化学特性。

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引用次数: 0