Solid oxide electrolysis cells (SOECs) exhibit remarkable efficiency in the production of syngas, a mixture of hydrogen and carbon monoxide, owing to their ability to electrolyze steam and carbon dioxide simultaneously. However, the polarization resistance associated with the gas diffusion process in the negatrode (fuel electrode) increases with increasing CO2 concentrations during steam/CO2 co-electrolysis. To reduce the gas diffusion resistance in negatrode-supported microtubular SOECs, acrylic resin and graphite are employed as pore formers in the negatrode. Replacing acrylic resin with graphite pore formers enhances the current density from 0.477 to 0.544 A cm−2 at H2O/CO2 = 2 and 700 °C owing to 22 % reduction in the polarization resistance associated with the gas diffusion process at low frequencies below 10 Hz. Focused ion beam-scanning electron microscopy analysis reveals that the fraction of small-pores (less than 2 μm in diameter) is higher in the cell employing the graphite pore former, which helps decrease the polarization resistance associated with the gas diffusion process in the negatrode. Thus, optimizing the negatrode microstructure is crucial to enhancing the performance of co-electrolysis SOECs.
固体氧化物电解电池（SOECs）在生产合成气（氢和一氧化碳的混合物）方面表现出显著的效率，因为它们能够同时电解蒸汽和二氧化碳。然而，在蒸汽/二氧化碳共电解过程中，负极（燃料电极）中与气体扩散过程相关的极化电阻随着CO2浓度的增加而增加。为了降低负极微管soec中的气体扩散阻力，在负极中使用丙烯酸树脂和石墨作为成孔剂。在H2O/CO2 = 2和700°C的条件下，石墨成孔材料的电流密度从0.477 A cm−2提高到0.544 A cm−2，这是由于在低于10 Hz的低频下，气体扩散过程中产生的极化电阻降低了22%。聚焦离子束扫描电镜分析表明，石墨成孔器的微孔（直径小于2 μm）比例较高，有利于降低负极中气体扩散过程的极化阻力。因此，优化负极结构对提高共电解soec的性能至关重要。
{"title":"Reduced gas diffusion resistance via modification of negatrode morphology for steam/CO2 co-electrolysis SOEC","authors":"Hirofumi Sumi , Mizuki Momai , Yohei Tanaka , Toshiaki Matsui","doi":"10.1016/j.elecom.2025.108022","DOIUrl":"10.1016/j.elecom.2025.108022","url":null,"abstract":"<div><div>Solid oxide electrolysis cells (SOECs) exhibit remarkable efficiency in the production of syngas, a mixture of hydrogen and carbon monoxide, owing to their ability to electrolyze steam and carbon dioxide simultaneously. However, the polarization resistance associated with the gas diffusion process in the negatrode (fuel electrode) increases with increasing CO<sub>2</sub> concentrations during steam/CO<sub>2</sub> co-electrolysis. To reduce the gas diffusion resistance in negatrode-supported microtubular SOECs, acrylic resin and graphite are employed as pore formers in the negatrode. Replacing acrylic resin with graphite pore formers enhances the current density from 0.477 to 0.544 A cm<sup>−2</sup> at H<sub>2</sub>O/CO<sub>2</sub> = 2 and 700 °C owing to 22 % reduction in the polarization resistance associated with the gas diffusion process at low frequencies below 10 Hz. Focused ion beam-scanning electron microscopy analysis reveals that the fraction of small-pores (less than 2 μm in diameter) is higher in the cell employing the graphite pore former, which helps decrease the polarization resistance associated with the gas diffusion process in the negatrode. Thus, optimizing the negatrode microstructure is crucial to enhancing the performance of co-electrolysis SOECs.</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"179 ","pages":"Article 108022"},"PeriodicalIF":4.2,"publicationDate":"2025-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144831450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tubular reactors offer increased surface-to-volume ratios compared to conventional planar reactors. Yet, they are seldom utilized in electrochemical applications. This is primarily due to the challenges associated with membrane placement and the lack of concepts for cell-stacking and integrating mixer elements in such designs. This study introduces two innovative tubular reactor designs which address these limitations, while the biphasic electrooxidation of hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) serves as case study: the Mixer Electrode Reactor (MER) and the Swiss-roll Reactor (SRR). The MER leverages a tubular 3D-printed stainless steel or nickel foam electrode to enhance mass transfer and active electrode area within the flow cell. The SRR, similar to spiral-wound membrane modules, employs a rolled-up assembly of nickel foam electrodes separated by polymeric spacers. In testing, the MER exhibited low FDCA yields (60%) due to an inhomogeneous electric field caused by non-uniform electrode spacing. In contrast, the SRR maintained a uniform electrode distance, resulting in a homogeneous electric field significantly improving performance. The SRR achieved higher FDCA yields (up to 73% at 15 mA cm−2) and significantly increased space–time yields (437 molFDCA m−3 h−1), surpassing both the MER and conventional planar reactor designs. This work highlights the potential of the SRR as an efficient and scalable tubular reactor, particularly for the integrated biphasic oxidation of HMF to FDCA.
与传统的平面反应器相比，管式反应器提供了更高的表面体积比。然而，它们很少用于电化学应用。这主要是由于与膜放置相关的挑战，以及在这种设计中缺乏细胞堆叠和集成混合器元素的概念。本研究介绍了两种创新的管式反应器设计，以解决这些限制，而两相电氧化羟甲基糠醛（HMF）到2,5-呋喃二羧酸（FDCA）作为案例研究：混合电极反应器（MER）和瑞士卷反应器（SRR）。MER利用管状3d打印不锈钢或镍泡沫电极来增强流体池内的传质和活性电极面积。SRR，类似于螺旋缠绕膜模块，采用由聚合物垫片分隔的镍泡沫电极的卷起来的组件。在测试中，由于非均匀电极间距引起的不均匀电场，MER表现出较低的FDCA产率（<60%）。相比之下，SRR保持了均匀的电极距离，导致均匀的电场显著提高了性能。SRR获得了更高的FDCA产率（在15 mA cm−2时高达73%），并且显著提高了时空产率（437 molFDCA m−3 h−1），超过了MER和传统的平面反应器设计。这项工作突出了SRR作为一种高效和可扩展的管式反应器的潜力，特别是对于HMF到FDCA的综合双相氧化。
{"title":"Tubular electrochemical reactors for the biphasic oxidation of HMF to FDCA","authors":"Tobias Harhues , Wenzel Plischka , Matthias Wessling , Robert Keller","doi":"10.1016/j.elecom.2025.108018","DOIUrl":"10.1016/j.elecom.2025.108018","url":null,"abstract":"<div><div>Tubular reactors offer increased surface-to-volume ratios compared to conventional planar reactors. Yet, they are seldom utilized in electrochemical applications. This is primarily due to the challenges associated with membrane placement and the lack of concepts for cell-stacking and integrating mixer elements in such designs. This study introduces two innovative tubular reactor designs which address these limitations, while the biphasic electrooxidation of hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) serves as case study: the Mixer Electrode Reactor (MER) and the Swiss-roll Reactor (SRR). The MER leverages a tubular 3D-printed stainless steel or nickel foam electrode to enhance mass transfer and active electrode area within the flow cell. The SRR, similar to spiral-wound membrane modules, employs a rolled-up assembly of nickel foam electrodes separated by polymeric spacers. In testing, the MER exhibited low FDCA yields (<span><math><mo><</mo></math></span>60%) due to an inhomogeneous electric field caused by non-uniform electrode spacing. In contrast, the SRR maintained a uniform electrode distance, resulting in a homogeneous electric field significantly improving performance. The SRR achieved higher FDCA yields (up to 73% at 15 mA cm<sup>−2</sup>) and significantly increased space–time yields (437 mol<sub>FDCA</sub> m<sup>−3</sup> h<sup>−1</sup>), surpassing both the MER and conventional planar reactor designs. This work highlights the potential of the SRR as an efficient and scalable tubular reactor, particularly for the integrated biphasic oxidation of HMF to FDCA.</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"179 ","pages":"Article 108018"},"PeriodicalIF":4.2,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144809985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-23DOI: 10.1016/j.elecom.2025.108009
Lin Wang , Hai Yu , YaXin Wang , Chun Miao , QianQian Lei , XinPing Yao , XiaoChen Yao , Xin Wei , JianGuo Lv , Yan Xue , JingWen Zhang , SiWen Zhou , DanDan Qu
This study synthesized p-type Cu2O using an electrodeposition method and firmly attached it to TiO2 nanosheets based on fluorine-doped tin oxide (FTO) substrates, forming a dense film that serves directly as a photoanode for photoelectrochemical (PEC) water splitting. Characterization techniques such as XRD, SEM, XPS, and UV–Vis confirmed the successful deposition of Cu2O on the TiO2 nanosheets, forming a p-n heterojunction structure. The incorporation of Cu2O effectively broadened the light absorption range of TiO2, with a cut-off wavelength red-shifting to 537 nm, enabling it to absorb more visible light. Photoelectrochemical tests showed that under illuminated unbiased conditions, the photocurrent density of Cu2O-TiO2 reached 0.3 mA/cm2, which is 7.5 times that of TiO2. After applying a small bias (0.5 V), the photocurrent density further increased to 2.1 mA/cm2, 5.2 times that under unbiased conditions, indicating that the introduction of electricity effectively accelerated the separation efficiency of photo-generated carriers. The Cu₂O-TiO₂ heterojunction exhibited significantly higher photocurrent density (measured by LSV) and charge transfer efficiency (evaluated by EIS) than pure TiO₂. This research provides new insights for PEC water splitting technology and serves as a reference for designing high-performance photocatalysts.
{"title":"Electrodeposition of p-type Cu2O on n-type TiO2 nanosheet arrays for enhanced photoelectrochemical water splitting","authors":"Lin Wang , Hai Yu , YaXin Wang , Chun Miao , QianQian Lei , XinPing Yao , XiaoChen Yao , Xin Wei , JianGuo Lv , Yan Xue , JingWen Zhang , SiWen Zhou , DanDan Qu","doi":"10.1016/j.elecom.2025.108009","DOIUrl":"10.1016/j.elecom.2025.108009","url":null,"abstract":"<div><div>This study synthesized p-type Cu<sub>2</sub>O using an electrodeposition method and firmly attached it to TiO<sub>2</sub> nanosheets based on fluorine-doped tin oxide (FTO) substrates, forming a dense film that serves directly as a photoanode for photoelectrochemical (PEC) water splitting. Characterization techniques such as XRD, SEM, XPS, and UV–Vis confirmed the successful deposition of Cu<sub>2</sub>O on the TiO<sub>2</sub> nanosheets, forming a p-n heterojunction structure. The incorporation of Cu<sub>2</sub>O effectively broadened the light absorption range of TiO<sub>2</sub>, with a cut-off wavelength red-shifting to 537 nm, enabling it to absorb more visible light. Photoelectrochemical tests showed that under illuminated unbiased conditions, the photocurrent density of Cu<sub>2</sub>O-TiO<sub>2</sub> reached 0.3 mA/cm<sup>2</sup>, which is 7.5 times that of TiO<sub>2</sub>. After applying a small bias (0.5 V), the photocurrent density further increased to 2.1 mA/cm<sup>2</sup>, 5.2 times that under unbiased conditions, indicating that the introduction of electricity effectively accelerated the separation efficiency of photo-generated carriers. The Cu₂O-TiO₂ heterojunction exhibited significantly higher photocurrent density (measured by LSV) and charge transfer efficiency (evaluated by EIS) than pure TiO₂. This research provides new insights for PEC water splitting technology and serves as a reference for designing high-performance photocatalysts.</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"178 ","pages":"Article 108009"},"PeriodicalIF":4.2,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-23DOI: 10.1016/j.elecom.2025.108007
Chuang Wang , Lidong You , Tingting Sun , Zichun Zhang
The two-dimensional W2C sparked widespread interest due to high physicochemical stability and large specific surface area. Fluoride-ion batteries (FIBs) are promising candidates in energy storage applications due to excellent properties such as high energy density. Despite such potential, the role of these materials in FIBs needs elucidation, especially regarding the effect of the fluoride ion transport mechanism on the material surface. In this study, the suitability of W2C as a cathode material for FIB was evaluated for the first time using the vacancy induction method based on first-principles calculations. The results show that the diffusion barrier for fluoride ions on the W2C surface is drastically reduced from 0.26 eV to 0.11 eV, and the ion transport efficiency is more than doubled, while a high theoretical voltage of 4.32 V and stable cycling at a concentration of 0–175 % F− are achieved. This is attributed to the fact that vacancy defects reduce the binding affinity of tungsten to fluoride ions and promote desorption of fluoride ions. This study highlights the importance of vacancy-induced techniques in enhancing 2D materials' ion transport capacity, providing valuable insights for advancing high-performance FIB designs.
{"title":"Two-dimensional W2C cathodes for fluoride-ion batteries: Achieving fast ion transport via vacancy induction","authors":"Chuang Wang , Lidong You , Tingting Sun , Zichun Zhang","doi":"10.1016/j.elecom.2025.108007","DOIUrl":"10.1016/j.elecom.2025.108007","url":null,"abstract":"<div><div>The two-dimensional W<sub>2</sub>C sparked widespread interest due to high physicochemical stability and large specific surface area. Fluoride-ion batteries (FIBs) are promising candidates in energy storage applications due to excellent properties such as high energy density. Despite such potential, the role of these materials in FIBs needs elucidation, especially regarding the effect of the fluoride ion transport mechanism on the material surface. In this study, the suitability of W<sub>2</sub>C as a cathode material for FIB was evaluated for the first time using the vacancy induction method based on first-principles calculations. The results show that the diffusion barrier for fluoride ions on the W<sub>2</sub>C surface is drastically reduced from 0.26 eV to 0.11 eV, and the ion transport efficiency is more than doubled, while a high theoretical voltage of 4.32 V and stable cycling at a concentration of 0–175 % F<sup>−</sup> are achieved. This is attributed to the fact that vacancy defects reduce the binding affinity of tungsten to fluoride ions and promote desorption of fluoride ions. This study highlights the importance of vacancy-induced techniques in enhancing 2D materials' ion transport capacity, providing valuable insights for advancing high-performance FIB designs.</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"179 ","pages":"Article 108007"},"PeriodicalIF":4.2,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144764059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-23DOI: 10.1016/j.elecom.2025.108010
Oluwasegun Emmanuel Ojodun, Patrick Ehi Imoisili, Tien-Chien Jen
This work studies the structural and electrochemical characteristics of nickel oxide (NiO) and nickel oxide/carbon nanotubes (NiO/CNT) nanocomposites prepared via spray pyrolysis and annealed at 350, 400, and 500 . Structural characterization using X-ray diffraction (XRD) confirms phase purity and crystallinity. The NiO and NiO/CNT samples annealed at 400 °C (400-N and 400-NCT) exhibited optimal performance. Scanning electron microscopy (SEM) images of 400-NCT revealed a compact morphology with well-dispersed CNTs across the NiO nanoparticles. From Brunauer-Emmett-Teller (BET) analysis, its specific surface area was 93.82 m2 g−1, broader than 400-N's 35.63 m2 g−1, while its pore volume was 0.43 cm3 g−1, larger than 0.13 cm3 g−1 for 400-N. Moreover, 400-NCT displayed higher specific capacitance of 745 F g−1 at 5 A g−1, better rate capability (30.7 %), and superior cycle life (109 % @ 1000 cycles) than 400-N (16.20 F g−1, 26 % rate retention, and 21 % longevity @ 1000 cycles) in 2 M KOH. From electrochemical impedance spectroscopy, 400-NCT portrayed the lowest series and charge transfer resistance (6.60 Ω; 2.28 Ω) than 400-N (7.83 Ω; 20.41 Ω), demonstrating enhanced conductivity. The synergistic combination of CNTs and NiO in the nanocomposite is responsible for the enhanced performance, which boosts the conductivity, enlarges the surface area, and optimizes the pore network for rapid ion transport and enhanced charge storage. These findings show how modifying a process parameter in a facile and affordable method like spray pyrolysis can yield optimal results, contributing to realizing Sustainable Development Goal 7 (SDG 7) of affordable and sustainable energy solutions.
{"title":"Thermal annealing-induced structural modifications and electrochemical enhancement of NiO/CNT electrodes synthesized by spray pyrolysis for high-performance supercapacitors","authors":"Oluwasegun Emmanuel Ojodun, Patrick Ehi Imoisili, Tien-Chien Jen","doi":"10.1016/j.elecom.2025.108010","DOIUrl":"10.1016/j.elecom.2025.108010","url":null,"abstract":"<div><div>This work studies the structural and electrochemical characteristics of nickel oxide (NiO) and nickel oxide/carbon nanotubes (NiO/CNT) nanocomposites prepared via spray pyrolysis and annealed at 350, 400, and 500 <span><math><mrow><msup><mrow></mrow><mo>°</mo></msup><mi>C</mi></mrow></math></span>. Structural characterization using X-ray diffraction (XRD) confirms phase purity and crystallinity. The NiO and NiO/CNT samples annealed at 400 °C (400-N and 400-NCT) exhibited optimal performance. Scanning electron microscopy (SEM) images of 400-NCT revealed a compact morphology with well-dispersed CNTs across the NiO nanoparticles. From Brunauer-Emmett-Teller (BET) analysis, its specific surface area was 93.82 m<sup>2</sup> g<sup>−1</sup>, broader than 400-N's 35.63 m<sup>2</sup> g<sup>−1</sup>, while its pore volume was 0.43 cm<sup>3</sup> g<sup>−1</sup>, larger than 0.13 cm<sup>3</sup> g<sup>−1</sup> for 400-N. Moreover, 400-NCT displayed higher specific capacitance of 745 F g<sup>−1</sup> at 5 A g<sup>−1</sup>, better rate capability (30.7 %), and superior cycle life (109 % @ 1000 cycles) than 400-N (16.20 F g<sup>−1</sup>, 26 % rate retention, and 21 % longevity @ 1000 cycles) in 2 M KOH. From electrochemical impedance spectroscopy, 400-NCT portrayed the lowest series and charge transfer resistance (6.60 Ω; 2.28 Ω) than 400-N (7.83 Ω; 20.41 Ω), demonstrating enhanced conductivity. The synergistic combination of CNTs and NiO in the nanocomposite is responsible for the enhanced performance, which boosts the conductivity, enlarges the surface area, and optimizes the pore network for rapid ion transport and enhanced charge storage. These findings show how modifying a process parameter in a facile and affordable method like spray pyrolysis can yield optimal results, contributing to realizing Sustainable Development Goal 7 (SDG 7) of affordable and sustainable energy solutions.</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"178 ","pages":"Article 108010"},"PeriodicalIF":4.7,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144714397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-23DOI: 10.1016/j.elecom.2025.108008
Basit Ali Khan , Fengqi Zhou , Tongsheng Zhang , Shams ur Rahman , Attia Sadiq , Farasat Haider , Fazila Shafique , Rafaqat Hussain , Jaweria Khalid
In this study, NiSe2/GO composites were successfully synthesized by using a facile and effective chemical method to increase the catalytic activity and charge transfer efficiency for oxygen evolution reaction (OER). The structural analysis confirmed the successful preparation of NiSe2 and NiSe2-GO (10 %, 25 %) composites. Similarly, the morphology of NiSe2 appeared to be nanocubes, whilst NiSe2-GO (10 %, 25 %) composites revealed features comprising of both NiSe2 nanocubes and GO sheets. The electrochemical performance of NiSe2 and NiSe2-GO (10 %, 25 %) composites was also investigated for enhanced OER. Among the synthesized compositions, NiSe2–25 % GO demonstrated the most superior electrocatalytic performance, which exhibited a significantly lower Tafel slope (66 mV/dec at 10 mV/s). Electrochemical impedance spectroscopy (EIS) analysis further confirmed the high efficiency of NiSe2–25 % GO, where a smallest semicircle in the Nyquist plot was observed. In terms of overpotential, NiSe2–25 % GO achieved a remarkably low value of ∼350 mV, demonstrating superior catalytic efficiency compared to NiSe2–10 % GO (∼500 mV) and pristine NiSe2 (∼600 mV). The significantly reduced overpotential suggested that the NiSe2–25 % GO material required the least energy input to drive the reaction at a given current density. This enhanced performance was attributed to the synergistic effect between NiSe2 and GO, where the GO matrix provided a favorable pathway for electron transfer, while NiSe2 acted as an active catalytic site for OER. These findings highlight NiSe2–25 % GO as a highly effective and promising electrocatalyst for OER applications. Its superior charge transport characteristics, lower overpotential, and faster reaction kinetics make it a strong candidate for next-generation energy conversion and storage technologies.
{"title":"Synthesis and exploration of NiSe2-GO composites as electrocatalysts with high-performance oxygen evolution reaction","authors":"Basit Ali Khan , Fengqi Zhou , Tongsheng Zhang , Shams ur Rahman , Attia Sadiq , Farasat Haider , Fazila Shafique , Rafaqat Hussain , Jaweria Khalid","doi":"10.1016/j.elecom.2025.108008","DOIUrl":"10.1016/j.elecom.2025.108008","url":null,"abstract":"<div><div>In this study, NiSe<sub>2</sub>/GO composites were successfully synthesized by using a facile and effective chemical method to increase the catalytic activity and charge transfer efficiency for oxygen evolution reaction (OER). The structural analysis confirmed the successful preparation of NiSe<sub>2</sub> and NiSe<sub>2</sub>-GO (10 %, 25 %) composites. Similarly, the morphology of NiSe<sub>2</sub> appeared to be nanocubes, whilst NiSe<sub>2</sub>-GO (10 %, 25 %) composites revealed features comprising of both NiSe<sub>2</sub> nanocubes and GO sheets. The electrochemical performance of NiSe<sub>2</sub> and NiSe<sub>2</sub>-GO (10 %, 25 %) composites was also investigated for enhanced OER. Among the synthesized compositions, NiSe<sub>2</sub>–25 % GO demonstrated the most superior electrocatalytic performance, which exhibited a significantly lower Tafel slope (66 mV/dec at 10 mV/s). Electrochemical impedance spectroscopy (EIS) analysis further confirmed the high efficiency of NiSe<sub>2</sub>–25 % GO, where a smallest semicircle in the Nyquist plot was observed. In terms of overpotential, NiSe<sub>2</sub>–25 % GO achieved a remarkably low value of ∼350 mV, demonstrating superior catalytic efficiency compared to NiSe<sub>2</sub>–10 % GO (∼500 mV) and pristine NiSe<sub>2</sub> (∼600 mV). The significantly reduced overpotential suggested that the NiSe<sub>2</sub>–25 % GO material required the least energy input to drive the reaction at a given current density. This enhanced performance was attributed to the synergistic effect between NiSe<sub>2</sub> and GO, where the GO matrix provided a favorable pathway for electron transfer, while NiSe<sub>2</sub> acted as an active catalytic site for OER. These findings highlight NiSe<sub>2</sub>–25 % GO as a highly effective and promising electrocatalyst for OER applications. Its superior charge transport characteristics, lower overpotential, and faster reaction kinetics make it a strong candidate for next-generation energy conversion and storage technologies.</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"179 ","pages":"Article 108008"},"PeriodicalIF":4.2,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144722280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-19DOI: 10.1016/j.elecom.2025.108001
Young Ji Park , Sang Hyo Jeong , Younki Lee , Tae Wook Kang , Sun Woog Kim
In this study, MnO2 was synthesized via a hydrothermal method using four different oxidizing agents: KMnO4, K2S2O8, KClO3, and (NH4)2S2O8. The KMnO4 precursor led to the formation of aggregated α-MnO₂, while K2S2O8 produced a mixed phase of α- and γ-MnO2. (NH4)2S2O8 promoted the formation of γ-MnO2 at lower temperatures and induced a structural transition to β-MnO2 at elevated temperatures. Among the lithium precursors investigated, LiOH was found to be the most effective in preserving the spherical morphology of LiMn2O4 during synthesis. Electrochemical measurements revealed that the LiMn2O4 sample synthesized from γ-MnO2 exhibited the highest charge capacity of 132.59 mAh∙g−1, while the α-MnO2-based LiMn2O4 demonstrated the best stability. These results indicate that the initial MnO2 phase significantly influences the electrochemical performance of the resulting spinel cathode.
{"title":"Phase- and morphology-controlled MnO2: Its synthesis and influence on the electrochemical performance of spinel LiMn2O4 cathode materials","authors":"Young Ji Park , Sang Hyo Jeong , Younki Lee , Tae Wook Kang , Sun Woog Kim","doi":"10.1016/j.elecom.2025.108001","DOIUrl":"10.1016/j.elecom.2025.108001","url":null,"abstract":"<div><div>In this study, MnO<sub>2</sub> was synthesized via a hydrothermal method using four different oxidizing agents: KMnO<sub>4</sub>, K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>, KClO<sub>3</sub>, and (NH<sub>4</sub>)<sub>2</sub>S<sub>2</sub>O<sub>8</sub>. The KMnO<sub>4</sub> precursor led to the formation of aggregated α-MnO₂, while K<sub>2</sub>S<sub>2</sub>O<sub>8</sub> produced a mixed phase of α- and γ-MnO<sub>2</sub>. (NH<sub>4</sub>)<sub>2</sub>S<sub>2</sub>O<sub>8</sub> promoted the formation of γ-MnO<sub>2</sub> at lower temperatures and induced a structural transition to β-MnO<sub>2</sub> at elevated temperatures. Among the lithium precursors investigated, LiOH was found to be the most effective in preserving the spherical morphology of LiMn<sub>2</sub>O<sub>4</sub> during synthesis. Electrochemical measurements revealed that the LiMn<sub>2</sub>O<sub>4</sub> sample synthesized from γ-MnO<sub>2</sub> exhibited the highest charge capacity of 132.59 mAh∙g<sup>−1</sup>, while the α-MnO<sub>2</sub>-based LiMn<sub>2</sub>O<sub>4</sub> demonstrated the best stability. These results indicate that the initial MnO<sub>2</sub> phase significantly influences the electrochemical performance of the resulting spinel cathode.</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"178 ","pages":"Article 108001"},"PeriodicalIF":4.7,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144686112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-07-18DOI: 10.1016/j.elecom.2025.108006
Yi Zhang , Chen Ji , Xingtian Wang , Bin Qiu , Huaiyu Chen
The development of cost-effective and high-performance electrochemical sensors for uric acid (UA) detection is critical due to its role as a key biomarker in disease diagnosis. This study presents an innovative sensor based on platinum nanoparticle (Pt NPs) decorated graphdiyne (GDY) nanohybrid (denoted as Pt NPs/GDY), fabricated via a facile electroless deposition method. The hybrid material capitalizes on the synergistic effects of GDY's π-electron-rich structure - enhancing target affinity through π-π stacking, and Pt NPs' dual functionality as conductivity boosters and catalytic activators. Electrochemical evaluations revealed that the Pt NPs/GDY-modified glassy carbon electrode (GCE) outperforms conventional GDY/GCE and bare GCE, achieving a broad linear range (0.1–7.5 μM) and an ultralow detection limit (30 nM). The sensor also demonstrated exceptional reproducibility, long-term stability, and selectivity against common interferents, validated by successful UA quantification in human urine samples (92.8–98.5 % recovery).
{"title":"Electrochemical detection of uric acid based on platinum nanoparticles/graphdiyne hybrids","authors":"Yi Zhang , Chen Ji , Xingtian Wang , Bin Qiu , Huaiyu Chen","doi":"10.1016/j.elecom.2025.108006","DOIUrl":"10.1016/j.elecom.2025.108006","url":null,"abstract":"<div><div>The development of cost-effective and high-performance electrochemical sensors for uric acid (UA) detection is critical due to its role as a key biomarker in disease diagnosis. This study presents an innovative sensor based on platinum nanoparticle (Pt NPs) decorated graphdiyne (GDY) nanohybrid (denoted as Pt NPs/GDY), fabricated via a facile electroless deposition method. The hybrid material capitalizes on the synergistic effects of GDY's π-electron-rich structure - enhancing target affinity through π-π stacking, and Pt NPs' dual functionality as conductivity boosters and catalytic activators. Electrochemical evaluations revealed that the Pt NPs/GDY-modified glassy carbon electrode (GCE) outperforms conventional GDY/GCE and bare GCE, achieving a broad linear range (0.1–7.5 μM) and an ultralow detection limit (30 nM). The sensor also demonstrated exceptional reproducibility, long-term stability, and selectivity against common interferents, validated by successful UA quantification in human urine samples (92.8–98.5 % recovery).</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"179 ","pages":"Article 108006"},"PeriodicalIF":4.2,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144764062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The spatial arrangement of biorecognition molecules on the sensor surface plays a critical role in determining the performance of electrochemical biosensors. In this work, we report a covalent and tunable immobilization strategy using aryl diazonium chemistry to functionalize carbon electrodes with ethynyl groups protected by trimethylsilyl (TMS) or triisopropylsilyl (TIPS) moieties. After deprotection, an azide-modified aptamer (APT) specific to diclofenac (DCF) was immobilized via copper-catalyzed azide–alkyne cycloaddition (CuAAC). Although the TMS and TIPS groups differ in size by only 1.7 Å, this small variation significantly influenced APT spacing and sensor performance. The TIPS-based sensor displayed a nearly fourfold increase in signal response compared to the TMS-based counterpart, achieving a limit of detection of 17.95 μM. These results underscore the importance of nanoscale molecular design in optimizing label-free aptasensor sensitivity.
{"title":"Surface organization of aptamers via diazonium grafting: A key parameter in label-free electrochemical sensing","authors":"Teodora Lupoi , Bogdan Feier , Florence Geneste , Cecilia Cristea , Yann R. Leroux","doi":"10.1016/j.elecom.2025.108000","DOIUrl":"10.1016/j.elecom.2025.108000","url":null,"abstract":"<div><div>The spatial arrangement of biorecognition molecules on the sensor surface plays a critical role in determining the performance of electrochemical biosensors. In this work, we report a covalent and tunable immobilization strategy using aryl diazonium chemistry to functionalize carbon electrodes with ethynyl groups protected by trimethylsilyl (TMS) or triisopropylsilyl (TIPS) moieties. After deprotection, an azide-modified aptamer (APT) specific to diclofenac (DCF) was immobilized via copper-catalyzed azide–alkyne cycloaddition (CuAAC). Although the TMS and TIPS groups differ in size by only 1.7 Å, this small variation significantly influenced APT spacing and sensor performance. The TIPS-based sensor displayed a nearly fourfold increase in signal response compared to the TMS-based counterpart, achieving a limit of detection of 17.95 μM. These results underscore the importance of nanoscale molecular design in optimizing label-free aptasensor sensitivity.</div></div>","PeriodicalId":304,"journal":{"name":"Electrochemistry Communications","volume":"178 ","pages":"Article 108000"},"PeriodicalIF":4.7,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144653705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号