Pub Date : 2024-02-01DOI: 10.3390/magnetochemistry10020009
A. Ivanova, Nelly S. Chmelyuk, A. Nikitin, Alexander G. Majouga, V. Chekhonin, M. Abakumov
Magnetic nanoparticles have gained attention as a potential structure for therapy and diagnosing oncological diseases. The key property of the magnetic nanoparticles is the ability to respond to an external magnetic field. It is known that magnetofection causes an increase in the cellular uptake of RNA and DNA in complexes with magnetic nanoparticles in the presence of a permanent magnetic field. However, the influence of a dynamic magnetic field on the internalization of MNPs is not clear. In this work, we propose the idea that applying external low-frequency dynamic magnetic fields may decrease the cellular uptake, such as macrophages and malignant neuroblastoma. Using fluorescence microscopy and atomic emission spectroscopy, we found that oscillating magnetic fields decreased the cellular uptake of magnetic nanoparticles compared to untreated cells by up to 46%. In SH-SY5Y tumor cells and macrophage RAW264.7 cells, the absolute values of Fe per cell differed by 0.10 pg/cell and 0.33 pg/cell between treated and untreated cells, respectively. These results can be applied in the control of the cellular uptake in different areas of biomedicine.
{"title":"Low-Frequency Dynamic Magnetic Fields Decrease Cellular Uptake of Magnetic Nanoparticles","authors":"A. Ivanova, Nelly S. Chmelyuk, A. Nikitin, Alexander G. Majouga, V. Chekhonin, M. Abakumov","doi":"10.3390/magnetochemistry10020009","DOIUrl":"https://doi.org/10.3390/magnetochemistry10020009","url":null,"abstract":"Magnetic nanoparticles have gained attention as a potential structure for therapy and diagnosing oncological diseases. The key property of the magnetic nanoparticles is the ability to respond to an external magnetic field. It is known that magnetofection causes an increase in the cellular uptake of RNA and DNA in complexes with magnetic nanoparticles in the presence of a permanent magnetic field. However, the influence of a dynamic magnetic field on the internalization of MNPs is not clear. In this work, we propose the idea that applying external low-frequency dynamic magnetic fields may decrease the cellular uptake, such as macrophages and malignant neuroblastoma. Using fluorescence microscopy and atomic emission spectroscopy, we found that oscillating magnetic fields decreased the cellular uptake of magnetic nanoparticles compared to untreated cells by up to 46%. In SH-SY5Y tumor cells and macrophage RAW264.7 cells, the absolute values of Fe per cell differed by 0.10 pg/cell and 0.33 pg/cell between treated and untreated cells, respectively. These results can be applied in the control of the cellular uptake in different areas of biomedicine.","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139878308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-01DOI: 10.3390/magnetochemistry10020008
Devashibhai Adroja, Dmitry Filippov
Magnetic materials are an important class of materials for the development of technology as well as for our fundamental understanding of microscopic magnetic interactions [...]
磁性材料是一类重要的材料,不仅有助于技术的发展,还有助于我们从根本上了解微观磁相互作用 [...]
{"title":"Magnetic and Magnetoelectric Materials","authors":"Devashibhai Adroja, Dmitry Filippov","doi":"10.3390/magnetochemistry10020008","DOIUrl":"https://doi.org/10.3390/magnetochemistry10020008","url":null,"abstract":"Magnetic materials are an important class of materials for the development of technology as well as for our fundamental understanding of microscopic magnetic interactions [...]","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139883184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-26DOI: 10.3390/magnetochemistry10020007
I. Malaescu, C. Marin, P. C. Fannin
Measurements of complex magnetic permeability, μ(f,H) = μ′(f,H) − iμ″(f,H) and dielectric permittivity ε(f,H) = ε′(f,H) − iε″(f,H), in the frequency range, f of (0.4–7) GHz, and polarizing field, H of (0–135) kA/m, were performed, for a kerosene-based ferrofluid with magnetite nanoparticles. Based on these measurements, the phenomenon of ferromagnetic resonance was highlighted and some microwave propagation parameters of the ferrofluid were determined: the attenuation constant, α(f,H), and the reflection coefficient, R(f,H), at the air-material interface, at the normal incidence. Knowing these parameters we proposed a theoretical model establishing for the first time an equation that allows the calculation of the overall reflection coefficient, Rw(f,H), at the normal incidence of the wave, for a ferrofluid of thickness d, deposited on a totally reflective support, following multiple internal reflections of the electromagnetic wave in the material. The results show that by increasing both, H, and d, the parameter, Rw(f,H) presents a minimum that decreases from 0.90 (for d = 2 mm) to 0.64 (for d = 10 mm), at frequency f = 5 GHz, which indicates an increase in the absorption of the electromagnetic wave by the ferrofluid. The obtained results are useful in the study of some materials that could be used as electromagnetic absorbers in the microwave range, by the determination of the overall reflection coefficient, Rw(f,H), controlled both by the thickness, d, of the absorber and by the external applied field, H.
在频率范围 f (0.4-7) GHz 和极化场 H (0-135) kA/m 下,对含有磁铁矿纳米颗粒的煤油基铁流体进行了复磁导率 μ(f,H) = μ′(f,H) - iμ″(f,H) 和介电导率 ε(f,H) = ε′(f,H) - iε″(f,H) 的测量。在这些测量的基础上,突出了铁磁共振现象,并确定了铁流体的一些微波传播参数:衰减常数 α(f,H) 和反射系数 R(f,H)。根据这些参数,我们提出了一个理论模型,首次建立了一个方程,可以计算出厚度为 d 的铁流体沉积在全反射支撑物上时,电磁波在材料中发生多次内部反射后,法线入射时的总反射系数 Rw(f,H)。结果表明,随着 H 和 d 的增加,Rw(f,H) 参数在频率 f = 5 GHz 时出现一个最小值,从 0.90(d = 2 mm 时)降至 0.64(d = 10 mm 时),这表明铁流体对电磁波的吸收增加了。通过测定由吸收体厚度 d 和外加磁场 H 控制的整体反射系数 Rw(f,H),所得结果有助于研究一些可用作微波范围内电磁吸收体的材料。
{"title":"Experimental Investigations on the Ferromagnetic Resonance and Absorbing Properties of a Ferrofluid in the Microwave Range","authors":"I. Malaescu, C. Marin, P. C. Fannin","doi":"10.3390/magnetochemistry10020007","DOIUrl":"https://doi.org/10.3390/magnetochemistry10020007","url":null,"abstract":"Measurements of complex magnetic permeability, μ(f,H) = μ′(f,H) − iμ″(f,H) and dielectric permittivity ε(f,H) = ε′(f,H) − iε″(f,H), in the frequency range, f of (0.4–7) GHz, and polarizing field, H of (0–135) kA/m, were performed, for a kerosene-based ferrofluid with magnetite nanoparticles. Based on these measurements, the phenomenon of ferromagnetic resonance was highlighted and some microwave propagation parameters of the ferrofluid were determined: the attenuation constant, α(f,H), and the reflection coefficient, R(f,H), at the air-material interface, at the normal incidence. Knowing these parameters we proposed a theoretical model establishing for the first time an equation that allows the calculation of the overall reflection coefficient, Rw(f,H), at the normal incidence of the wave, for a ferrofluid of thickness d, deposited on a totally reflective support, following multiple internal reflections of the electromagnetic wave in the material. The results show that by increasing both, H, and d, the parameter, Rw(f,H) presents a minimum that decreases from 0.90 (for d = 2 mm) to 0.64 (for d = 10 mm), at frequency f = 5 GHz, which indicates an increase in the absorption of the electromagnetic wave by the ferrofluid. The obtained results are useful in the study of some materials that could be used as electromagnetic absorbers in the microwave range, by the determination of the overall reflection coefficient, Rw(f,H), controlled both by the thickness, d, of the absorber and by the external applied field, H.","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139595115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tactile sensory organs for three-dimensional (3D) force perception are essential for most living organisms and enable them to perform complex and sophisticated tasks to survive and evolve. Magnetic-based tactile sensors have been developed rapidly in recent years due to the exploitability of 3D force decoupling. Here, a method of magnet splicing is introduced, which can be applied to a magnetic tactile sensor to realize 3D self-decoupling of magnets’ displacements. This method enables the magnets to produce a completely consistent magnetic field distribution as the ideal magnetization model within a certain working range, eliminating the compensation and correction of the 3D magnetic flux density signal. This method carves out a new way for the practical application of 3D decoupling theory, showcasing the great potential in the fields of magnetic sensors and magnetic actuators.
{"title":"A Magnet Splicing Method for Constructing a Three-Dimensional Self-Decoupled Magnetic Tactile Sensor","authors":"Huangzhe Dai, Zheyan Wu, Chenxian Meng, Chengqian Zhang, Peng Zhao","doi":"10.3390/magnetochemistry10010006","DOIUrl":"https://doi.org/10.3390/magnetochemistry10010006","url":null,"abstract":"Tactile sensory organs for three-dimensional (3D) force perception are essential for most living organisms and enable them to perform complex and sophisticated tasks to survive and evolve. Magnetic-based tactile sensors have been developed rapidly in recent years due to the exploitability of 3D force decoupling. Here, a method of magnet splicing is introduced, which can be applied to a magnetic tactile sensor to realize 3D self-decoupling of magnets’ displacements. This method enables the magnets to produce a completely consistent magnetic field distribution as the ideal magnetization model within a certain working range, eliminating the compensation and correction of the 3D magnetic flux density signal. This method carves out a new way for the practical application of 3D decoupling theory, showcasing the great potential in the fields of magnetic sensors and magnetic actuators.","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139609770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A diatomaceous earth (DE)-based adsorbent DE-Ce was prepared and optimized to remove phosphorus from wastewater. DE was modified through purification–cerium loading, improving its phosphorus adsorption capacity and recycling ability. The preparation conditions were optimized using the Box–Behnken design, and the response surface method was employed to analyze the effects of roasting temperature, cerium concentration, and HCl concentration on the preparation of DE-Ce. Scanning electron microscopy, X-ray fluorescence spectrometry, and X-ray photoelectron spectroscopy were used for characterization, with results indicating that HCl washing can effectively remove impurities. Cerium was mainly loaded onto DE in the form of Ce(OH)3, and pore size and capacity increased following cerium loading, with the formation of a macroporous structure. The obtained DE-Ce adsorbent removed 98.30% phosphorous, with the removal process following the secondary kinetic and Langmuir models. According to material characterization and model analysis results, the phosphorus removal mechanism primarily involves electrostatic adsorption, ligand exchange, and precipitation. Overall, the findings indicate that cerium modification can effectively improve the adsorption capacity of DE.
制备并优化了一种基于硅藻土(DE)的吸附剂 DE-Ce,用于去除废水中的磷。通过对硅藻土进行纯化-铈负载改性,提高了其对磷的吸附能力和循环利用能力。采用 Box-Behnken 设计优化了制备条件,并采用响应面法分析了焙烧温度、铈浓度和盐酸浓度对 DE-Ce 制备的影响。采用扫描电子显微镜、X 射线荧光光谱和 X 射线光电子能谱进行表征,结果表明盐酸洗涤能有效去除杂质。铈主要以 Ce(OH)3 的形式负载到 DE 上,负载铈后孔径和容量增加,并形成大孔结构。得到的 DE-Ce 吸附剂对磷的去除率为 98.30%,去除过程遵循二级动力学和 Langmuir 模型。根据材料表征和模型分析结果,除磷机理主要包括静电吸附、配体交换和沉淀。总之,研究结果表明,铈改性可有效提高 DE 的吸附能力。
{"title":"Preparation and Optimization of the Adsorbent for Phosphorus Removal Using the Response Surface Method","authors":"Zhanmei Zhang, Zuqin Zou, Xiaoyu Ren, Yunxuan Huang, Yang Deng, Huaili Zheng","doi":"10.3390/magnetochemistry10010005","DOIUrl":"https://doi.org/10.3390/magnetochemistry10010005","url":null,"abstract":"A diatomaceous earth (DE)-based adsorbent DE-Ce was prepared and optimized to remove phosphorus from wastewater. DE was modified through purification–cerium loading, improving its phosphorus adsorption capacity and recycling ability. The preparation conditions were optimized using the Box–Behnken design, and the response surface method was employed to analyze the effects of roasting temperature, cerium concentration, and HCl concentration on the preparation of DE-Ce. Scanning electron microscopy, X-ray fluorescence spectrometry, and X-ray photoelectron spectroscopy were used for characterization, with results indicating that HCl washing can effectively remove impurities. Cerium was mainly loaded onto DE in the form of Ce(OH)3, and pore size and capacity increased following cerium loading, with the formation of a macroporous structure. The obtained DE-Ce adsorbent removed 98.30% phosphorous, with the removal process following the secondary kinetic and Langmuir models. According to material characterization and model analysis results, the phosphorus removal mechanism primarily involves electrostatic adsorption, ligand exchange, and precipitation. Overall, the findings indicate that cerium modification can effectively improve the adsorption capacity of DE.","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139443362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-02DOI: 10.3390/magnetochemistry10010004
C. Marin, I. Malaescu
The magnetic permeability (μ), dielectric permittivity (ε) and electrical conductivity (σ) of six elastomer samples obtained by mixing silicone rubber (RTV-530) with a kerosene-based ferrofluid in different volume fractions (φ), 1.31%, 2.59% and 3.84%, were determined using complex impedance measurements over a frequency range of 500 Hz–2 MHz. Three samples (A0, B0 and C0) were manufactured in the absence of a magnetic field, and the other three samples (Ah, Bh and Ch) were manufactured in the presence of a magnetic field, H = 43 kA/m. The component μ″ of the complex effective magnetic permeability of all samples presents a maximum at a frequency, fmax, that moves to higher values by increasing φ, with this maximum being attributed to Brownian relaxation processes. The conductivity spectrum, σ (f), of all samples follows the Jonscher universal law, which allows for both the determination of the static conductivity, σDC, and the barrier energy of the electrical conduction process, Wm. For the same φ, Wm is lower, and σDC is higher in the samples Ah, Bh and Ch than in the samples A0, B0 and C0. The performed study is useful in manufacturing elastomers with predetermined properties and for possible applications such as magneto-dielectric flexible electronic devices, which can be controlled by the volume fraction of particles or by an external magnetic field.
{"title":"The Effect of Magnetically Induced Local Structure and Volume Fraction on the Electromagnetic Properties of Elastomer Samples with Ferrofluid Droplet Inserts","authors":"C. Marin, I. Malaescu","doi":"10.3390/magnetochemistry10010004","DOIUrl":"https://doi.org/10.3390/magnetochemistry10010004","url":null,"abstract":"The magnetic permeability (μ), dielectric permittivity (ε) and electrical conductivity (σ) of six elastomer samples obtained by mixing silicone rubber (RTV-530) with a kerosene-based ferrofluid in different volume fractions (φ), 1.31%, 2.59% and 3.84%, were determined using complex impedance measurements over a frequency range of 500 Hz–2 MHz. Three samples (A0, B0 and C0) were manufactured in the absence of a magnetic field, and the other three samples (Ah, Bh and Ch) were manufactured in the presence of a magnetic field, H = 43 kA/m. The component μ″ of the complex effective magnetic permeability of all samples presents a maximum at a frequency, fmax, that moves to higher values by increasing φ, with this maximum being attributed to Brownian relaxation processes. The conductivity spectrum, σ (f), of all samples follows the Jonscher universal law, which allows for both the determination of the static conductivity, σDC, and the barrier energy of the electrical conduction process, Wm. For the same φ, Wm is lower, and σDC is higher in the samples Ah, Bh and Ch than in the samples A0, B0 and C0. The performed study is useful in manufacturing elastomers with predetermined properties and for possible applications such as magneto-dielectric flexible electronic devices, which can be controlled by the volume fraction of particles or by an external magnetic field.","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139391467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-24DOI: 10.3390/magnetochemistry10010002
M. Molčan, A. Skumiel, Jana Tóthová, K. Paulovičová, P. Kopčanský, M. Timko
High-frequency components such as microprocessors, transistors, antennas, voltage-controlled oscillators, and many others generate a large amount of heat. In the absence of satisfactory cooling, these components may suffer damage or even destruction. Therefore, it is important to find effective ways to cool these components. A possible solution is to use oil-based magnetic fluids. Magnetic fluids contain magnetic particles dispersed in oil, and their properties, including viscosity, affect their cooling capabilities. Viscosity can be changed by adding various additives or by adjusting the concentration of magnetic particles. The advantage of using oil-based magnetic fluids for cooling is that they allow for precise dosing and control of the amount of fluid applied to the component, reducing thermal losses and increasing cooling efficiency. In addition, oil-based magnetic fluids can also act as a dielectric, reducing electrical noise and increasing electromagnetic compatibility with the components. Analyzing the heating rate of magnetic fluids consisting of mineral oils in an alternating magnetic field with a frequency of 500 kHz, we have shown the capability of controlling thermal losses by adjusting the viscosity of the carrier liquid.
{"title":"The Influence of Viscosity on Heat Dissipation under Conditions of the High-Frequency Oscillating Magnetic Field","authors":"M. Molčan, A. Skumiel, Jana Tóthová, K. Paulovičová, P. Kopčanský, M. Timko","doi":"10.3390/magnetochemistry10010002","DOIUrl":"https://doi.org/10.3390/magnetochemistry10010002","url":null,"abstract":"High-frequency components such as microprocessors, transistors, antennas, voltage-controlled oscillators, and many others generate a large amount of heat. In the absence of satisfactory cooling, these components may suffer damage or even destruction. Therefore, it is important to find effective ways to cool these components. A possible solution is to use oil-based magnetic fluids. Magnetic fluids contain magnetic particles dispersed in oil, and their properties, including viscosity, affect their cooling capabilities. Viscosity can be changed by adding various additives or by adjusting the concentration of magnetic particles. The advantage of using oil-based magnetic fluids for cooling is that they allow for precise dosing and control of the amount of fluid applied to the component, reducing thermal losses and increasing cooling efficiency. In addition, oil-based magnetic fluids can also act as a dielectric, reducing electrical noise and increasing electromagnetic compatibility with the components. Analyzing the heating rate of magnetic fluids consisting of mineral oils in an alternating magnetic field with a frequency of 500 kHz, we have shown the capability of controlling thermal losses by adjusting the viscosity of the carrier liquid.","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139159916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-20DOI: 10.3390/magnetochemistry10010001
Laura C. J. Pereira, D. Belo
In the commemorative Special Issue titled “Insights into Functional Molecular Materials—A Themed Collection Honoring Professor Manuel Almeida on His 70th Birthday”, eminent researchers from around the globe in the field of molecular materials science come together to acknowledge and celebrate the notable scientific contributions of Professor Almeida [...]
{"title":"Functional Molecular Materials Insights","authors":"Laura C. J. Pereira, D. Belo","doi":"10.3390/magnetochemistry10010001","DOIUrl":"https://doi.org/10.3390/magnetochemistry10010001","url":null,"abstract":"In the commemorative Special Issue titled “Insights into Functional Molecular Materials—A Themed Collection Honoring Professor Manuel Almeida on His 70th Birthday”, eminent researchers from around the globe in the field of molecular materials science come together to acknowledge and celebrate the notable scientific contributions of Professor Almeida [...]","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139168810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-18DOI: 10.3390/magnetochemistry9120233
Yen-Ju Chen, Yan-Hom Li, Ching-Yao Chen
In comparison to alternative methods for hydrogen production, water electrolysis stands out as the optimal means for obtaining ultra-pure hydrogen. However, its widespread adoption is significantly hampered by its low energy efficiency. It has been established that the introduction of an external magnetic field can mitigate energy consumption, consequently enhancing electrolysis efficiency. While much of the research has revealed that an electrode–parallel magnetic field plays a crucial role in enhancing the bubble detachment process, there has been limited exploration of the effect of electrode–normal magnetic fields. In this work, we compare the water electrolysis efficiency of a circular electrode subjected to electrode–normal magnetic field resulting in a magnet edge effect and electrode edge effect by varying the sizes of the magnet and electrode. The findings indicate that a rotational flow caused by the Lorentz force facilitates the detachment of the hydrogen from the electrode surface. However, the rotation direction of hydrogen gas bubbles generated by the magnet edge effect is opposite to that of electrode edge effect. Furthermore, the magnet edge effect has more significant influence on the hydrogen bubbles’ locomotion than the electrode edge effect. With an electrode gap of 30 mm, employing the magnet edge effect generated by a single magnet leads to an average of 4.9% increase in current density. On the other hand, the multiple magnet effects created by multiple small magnets under the electrode can further result in an average 6.6% increase in current density. Nevertheless, at an electrode spacing of 50 mm, neither the magnet edge effect nor the electrode edge effect demonstrates a notable enhancement in conductivity. In reality, the electrode edge effect even leads to a reduction in conductivity.
{"title":"Effect of Electrode–Normal Magnetic Field on the Motion of Hydrogen Bubbles","authors":"Yen-Ju Chen, Yan-Hom Li, Ching-Yao Chen","doi":"10.3390/magnetochemistry9120233","DOIUrl":"https://doi.org/10.3390/magnetochemistry9120233","url":null,"abstract":"In comparison to alternative methods for hydrogen production, water electrolysis stands out as the optimal means for obtaining ultra-pure hydrogen. However, its widespread adoption is significantly hampered by its low energy efficiency. It has been established that the introduction of an external magnetic field can mitigate energy consumption, consequently enhancing electrolysis efficiency. While much of the research has revealed that an electrode–parallel magnetic field plays a crucial role in enhancing the bubble detachment process, there has been limited exploration of the effect of electrode–normal magnetic fields. In this work, we compare the water electrolysis efficiency of a circular electrode subjected to electrode–normal magnetic field resulting in a magnet edge effect and electrode edge effect by varying the sizes of the magnet and electrode. The findings indicate that a rotational flow caused by the Lorentz force facilitates the detachment of the hydrogen from the electrode surface. However, the rotation direction of hydrogen gas bubbles generated by the magnet edge effect is opposite to that of electrode edge effect. Furthermore, the magnet edge effect has more significant influence on the hydrogen bubbles’ locomotion than the electrode edge effect. With an electrode gap of 30 mm, employing the magnet edge effect generated by a single magnet leads to an average of 4.9% increase in current density. On the other hand, the multiple magnet effects created by multiple small magnets under the electrode can further result in an average 6.6% increase in current density. Nevertheless, at an electrode spacing of 50 mm, neither the magnet edge effect nor the electrode edge effect demonstrates a notable enhancement in conductivity. In reality, the electrode edge effect even leads to a reduction in conductivity.","PeriodicalId":18194,"journal":{"name":"Magnetochemistry","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139173816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}