Pub Date : 2024-09-21DOI: 10.1007/s10971-024-06549-9
Faouzia Tayari, Silvia Soreto Teixeira, M. P. F. Graça, Manel Essid, Kais Iben Nassar
The goal of this research is to create a perovskite ceramic with electrical and dielectric properties appropriate for energy storage, medical uses, and electronic devices. A bismuth ferric titanate, Bi0.7Ba0.3(FeTi)0.5O3, doped with barium and crystalline, was effectively synthesized at the A-site via sol–gel synthesis. A rhombohedral structure emerged in the R3́C space group, which was confirmed by room-temperature X-ray studies. An average grain size of 263 nm and a homogeneous grain distribution and chemical composition were confirmed by the results of scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The study established a clear relationship between temperature, frequency, and the electrical properties of the material. Impedance spectroscopy and electrical modulus measurements, performed in the frequency range of 1 kHz to 1 MHz and at temperatures ranging from 200 K to 360 K, demonstrated a non-Debye type of relaxation. Furthermore, once the material was produced at various temperatures, its frequency-dependent electrical conductivity was examined using Jonscher’s law. The results demonstrate that barium doping significantly improves the electrical conductivity and dielectric properties compared to pure BiFeTiO₃. Over the complete temperature range, consistent conduction and relaxation mechanisms were discovered. These findings suggest that the chemical may find widespread applicability across a broad temperature range, including electrical fields and capacitors.
Graphical Abstract
这项研究的目标是创造出一种具有适合能量储存、医疗用途和电子设备的电气和介电特性的过氧化物陶瓷。通过溶胶-凝胶合成法，在 A 位有效合成了一种掺杂钡的结晶钛酸铁铋（Bi0.7Ba0.3(FeTi)0.5O3）。室温 X 射线研究证实，该化合物具有 R3́C 空间群的斜方体结构。扫描电子显微镜（SEM）和能量色散 X 射线分析（EDX）的结果证实了平均粒度为 263 nm、均匀的晶粒分布和化学成分。研究在温度、频率和材料的电特性之间建立了明确的关系。在 1 kHz 至 1 MHz 的频率范围和 200 K 至 360 K 的温度范围内进行的阻抗光谱和电模量测量显示了非德拜类型的弛豫。此外，在不同温度下生产出这种材料后，还利用容舍定律对其随频率变化的导电性进行了研究。结果表明，与纯 BiFeTiO₃ 相比，钡掺杂显著提高了导电性和介电特性。在整个温度范围内，发现了一致的传导和弛豫机制。这些研究结果表明，这种化学物质可能会在广泛的温度范围内得到广泛应用，包括电场和电容器。
{"title":"Investigating structural, dielectric, and electrical characteristics of sol–gel synthesized perovskite ceramic Bi0.7Ba0.3(FeTi)0.5O3","authors":"Faouzia Tayari, Silvia Soreto Teixeira, M. P. F. Graça, Manel Essid, Kais Iben Nassar","doi":"10.1007/s10971-024-06549-9","DOIUrl":"10.1007/s10971-024-06549-9","url":null,"abstract":"<div><p>The goal of this research is to create a perovskite ceramic with electrical and dielectric properties appropriate for energy storage, medical uses, and electronic devices. A bismuth ferric titanate, Bi<sub>0.7</sub>Ba<sub>0.3</sub>(FeTi)<sub>0.5</sub>O<sub>3</sub>, doped with barium and crystalline, was effectively synthesized at the A-site via sol–gel synthesis. A rhombohedral structure emerged in the R3́C space group, which was confirmed by room-temperature X-ray studies. An average grain size of 263 nm and a homogeneous grain distribution and chemical composition were confirmed by the results of scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The study established a clear relationship between temperature, frequency, and the electrical properties of the material. Impedance spectroscopy and electrical modulus measurements, performed in the frequency range of 1 kHz to 1 MHz and at temperatures ranging from 200 K to 360 K, demonstrated a non-Debye type of relaxation. Furthermore, once the material was produced at various temperatures, its frequency-dependent electrical conductivity was examined using Jonscher’s law. The results demonstrate that barium doping significantly improves the electrical conductivity and dielectric properties compared to pure BiFeTiO₃. Over the complete temperature range, consistent conduction and relaxation mechanisms were discovered. These findings suggest that the chemical may find widespread applicability across a broad temperature range, including electrical fields and capacitors.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 2","pages":"601 - 613"},"PeriodicalIF":2.3,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10971-024-06549-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142540644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The synthesis and characterization of novel p-type copper delafossite CuBO2 microstructures were performed using an eco-friendly and cost-effective hydrothermal process. This study aims to explore the potential of these microstructures for environmental applications, specifically in the photo-induced degradation of hazardous dyes in wastewater. Various growth times were investigated to determine their influence on the morphology and photocatalytic performance of the synthesized microstructures. The characterization was carried out using X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM), and transmission electron microscope (TEM). The energy dispersive X-ray (EDX) studies and UV-Vis spectrophotometer were used to analyze the optical properties and compositional purity. The synthesized CuBO2 microstructures demonstrated significant photocatalytic activity, with the optimal sample synthesized in 2 h exhibiting a high degradation rate constant of 0.263 min−1, it was found that the materials synthesized for the ideal 2 h exhibited good photocatalytic activity. The results indicated that the photocatalytic activity of the CuBO₂ samples improved with increasing growth time, attributed to the enhanced crystallinity and larger surface area of the microstructures. Moreover, The findings suggest that these hierarchical microstructures have a strong potential for use in wastewater treatment applications. This work indicates that CuBO2 can be a versatile and effective material for environmental remediation, highlighting its importance in developing sustainable solutions for pollution control.
Graphical Abstract
本研究采用环保且经济高效的水热法合成了新型 p 型铜 delafossite CuBO2 微结构，并对其进行了表征。本研究旨在探索这些微结构在环境应用方面的潜力，特别是在光诱导降解废水中的有害染料方面。研究了不同的生长时间，以确定它们对合成微结构的形态和光催化性能的影响。表征采用了 X 射线衍射仪（XRD）、场发射扫描电子显微镜（FESEM）和透射电子显微镜（TEM）。能量色散 X 射线（EDX）研究和紫外可见分光光度计用于分析光学特性和成分纯度。合成的 CuBO2 微结构表现出显著的光催化活性，2 h 内合成的最佳样品表现出 0.263 min-1 的高降解速率常数，发现理想的 2 h 内合成的材料表现出良好的光催化活性。结果表明，CuBO₂样品的光催化活性随着生长时间的延长而提高，这归因于微结构的结晶度提高和比表面积增大。此外，研究结果表明，这些分层微结构在废水处理应用中具有很大的潜力。这项研究表明，CuBO2 是一种多功能、有效的环境修复材料，在开发可持续的污染控制解决方案方面具有重要意义。
{"title":"Effect of synthesis time on the photocatalytic performance of aggregated CuBO₂ microstructures for photo induced hazardous dye removal","authors":"Angshuman Majumdar, Sudipta Chatterjee, Arighna Basak","doi":"10.1007/s10971-024-06554-y","DOIUrl":"10.1007/s10971-024-06554-y","url":null,"abstract":"<div><p>The synthesis and characterization of novel p-type copper delafossite CuBO<sub>2</sub> microstructures were performed using an eco-friendly and cost-effective hydrothermal process. This study aims to explore the potential of these microstructures for environmental applications, specifically in the photo-induced degradation of hazardous dyes in wastewater. Various growth times were investigated to determine their influence on the morphology and photocatalytic performance of the synthesized microstructures. The characterization was carried out using X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM), and transmission electron microscope (TEM). The energy dispersive X-ray (EDX) studies and UV-Vis spectrophotometer were used to analyze the optical properties and compositional purity. The synthesized CuBO<sub>2</sub> microstructures demonstrated significant photocatalytic activity, with the optimal sample synthesized in 2 h exhibiting a high degradation rate constant of 0.263 min<sup>−1</sup>, it was found that the materials synthesized for the ideal 2 h exhibited good photocatalytic activity. The results indicated that the photocatalytic activity of the CuBO₂ samples improved with increasing growth time, attributed to the enhanced crystallinity and larger surface area of the microstructures. Moreover, The findings suggest that these hierarchical microstructures have a strong potential for use in wastewater treatment applications. This work indicates that CuBO<sub>2</sub> can be a versatile and effective material for environmental remediation, highlighting its importance in developing sustainable solutions for pollution control.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 2","pages":"582 - 593"},"PeriodicalIF":2.3,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142540570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-20DOI: 10.1007/s10971-024-06544-0
Hongwei Yan, Taixiang Liu, Lin Huang, Ke Yang, Changpeng Li, Zhuo Zhang, Yujie Qian
Silica sol-gel antireflection coatings are used in high-power lasers due to their excellent laser damage resistance. These coatings are prepared using silica nanoparticles, and flaws generated during the coating preparation process are considered one of the factors that can lead to laser damage. Ring-shape flaws of micrometer-size usually appear on the surface of silica sol-gel antireflection coating. The morphologies of these flaws were investigated through optical microscopy, contact-type surface profilometer and scanning electron microscope. The diameters of the ring-shape flaws are from several micrometers to tens of micrometers. It has been demonstrated that the ring-shape flaws are nodule-like structures containing closely packed silica nanoparticles. The quasi-in-situ laser damage tests of the coated samples show the ring-shape flaws have a low damage probability. The formation of ring-shape flaws on the silica sol-gel coating is related to the polydispersity of the colloidal silica nanoparticles. Through the analysis of the size distribution of silica nanoparticles, a mechanism for flaws formation is proposed.
{"title":"Quasi-in-situ characterization and laser damage investigation of flaws in silica antireflection coatings","authors":"Hongwei Yan, Taixiang Liu, Lin Huang, Ke Yang, Changpeng Li, Zhuo Zhang, Yujie Qian","doi":"10.1007/s10971-024-06544-0","DOIUrl":"10.1007/s10971-024-06544-0","url":null,"abstract":"<p>Silica sol-gel antireflection coatings are used in high-power lasers due to their excellent laser damage resistance. These coatings are prepared using silica nanoparticles, and flaws generated during the coating preparation process are considered one of the factors that can lead to laser damage. Ring-shape flaws of micrometer-size usually appear on the surface of silica sol-gel antireflection coating. The morphologies of these flaws were investigated through optical microscopy, contact-type surface profilometer and scanning electron microscope. The diameters of the ring-shape flaws are from several micrometers to tens of micrometers. It has been demonstrated that the ring-shape flaws are nodule-like structures containing closely packed silica nanoparticles. The quasi-in-situ laser damage tests of the coated samples show the ring-shape flaws have a low damage probability. The formation of ring-shape flaws on the silica sol-gel coating is related to the polydispersity of the colloidal silica nanoparticles. Through the analysis of the size distribution of silica nanoparticles, a mechanism for flaws formation is proposed.</p>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 2","pages":"594 - 600"},"PeriodicalIF":2.3,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142540569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-19DOI: 10.1007/s10971-024-06551-1
Nicolas Perciani de Moraes, Pedro Malavota Ribeiro, Bruno Henrique Baena da Silva, Tiago Moreira Bastos Campos, Gilmar Patrocínio Thim, Marcos Roberto de Vasconcelos Lanza, Liana Alvares Rodrigues
This study investigated the suitability of multiple bismuth sulfide (Bi2S3) samples for the photoreduction of Cr(VI) under simulated sunlight, aiming to elucidate the effect of different sulfide sources (thiourea, thioacetamide, sodium sulfide, potassium sulfide, and ammonium sulfide) on the final structural and photocatalytic properties of this semiconductor. The sulfides were produced through simple precipitation methods, without the necessity of complex methodologies or equipment. Additionally, the effect of thermal treatment on the properties of the Bi2S3 samples was also evaluated. The choice of the sulfide precursor imparted distinct characteristics onto the synthesized Bi2S3, such as distinct morphologies, specific surface areas (SSA), and crystalline structures. Notably, the efficiency of Cr(VI) photoreduction was found to be intricately linked to the adsorption capacity of Bi2S3. In this context, the calcination process emerged as a significant impediment, as it substantially diminished both the SSA and adsorption capacity of the materials. Among the sulfide sources investigated, Bi2S3 synthesized using K2S exhibited superior photoreduction efficiency, attributed primarily to its remarkable adsorption capacity and rod-like morphology. The photoreduction mechanism was determined to be carried out by the direct reaction between Cr(VI) and photogenerated electrons. Regarding operational parameters, initial concentration, pH and temperature had major effects on the photoreduction efficiency; high initial concentrations led to the saturation of the active sites and lower reaction rate constants, whereas lower pHs and higher temperatures favored the photoreduction process. As for the recycle tests of the best photocatalyst, it was discovered a significant efficiency loss between cycles, which was linked to the occlusion of active sites through the formation of chrome-based species on the surface of the photocatalyst.
{"title":"Bi2S3 for sunlight-based Cr(VI) photoreduction: investigating the effect of sulfur precursor on its structural and photocatalytic properties","authors":"Nicolas Perciani de Moraes, Pedro Malavota Ribeiro, Bruno Henrique Baena da Silva, Tiago Moreira Bastos Campos, Gilmar Patrocínio Thim, Marcos Roberto de Vasconcelos Lanza, Liana Alvares Rodrigues","doi":"10.1007/s10971-024-06551-1","DOIUrl":"10.1007/s10971-024-06551-1","url":null,"abstract":"<div><p>This study investigated the suitability of multiple bismuth sulfide (Bi<sub>2</sub>S<sub>3</sub>) samples for the photoreduction of Cr(VI) under simulated sunlight, aiming to elucidate the effect of different sulfide sources (thiourea, thioacetamide, sodium sulfide, potassium sulfide, and ammonium sulfide) on the final structural and photocatalytic properties of this semiconductor. The sulfides were produced through simple precipitation methods, without the necessity of complex methodologies or equipment. Additionally, the effect of thermal treatment on the properties of the Bi<sub>2</sub>S<sub>3</sub> samples was also evaluated. The choice of the sulfide precursor imparted distinct characteristics onto the synthesized Bi<sub>2</sub>S<sub>3</sub>, such as distinct morphologies, specific surface areas (SSA), and crystalline structures. Notably, the efficiency of Cr(VI) photoreduction was found to be intricately linked to the adsorption capacity of Bi<sub>2</sub>S<sub>3</sub>. In this context, the calcination process emerged as a significant impediment, as it substantially diminished both the SSA and adsorption capacity of the materials. Among the sulfide sources investigated, Bi<sub>2</sub>S<sub>3</sub> synthesized using K<sub>2</sub>S exhibited superior photoreduction efficiency, attributed primarily to its remarkable adsorption capacity and rod-like morphology. The photoreduction mechanism was determined to be carried out by the direct reaction between Cr(VI) and photogenerated electrons. Regarding operational parameters, initial concentration, pH and temperature had major effects on the photoreduction efficiency; high initial concentrations led to the saturation of the active sites and lower reaction rate constants, whereas lower pHs and higher temperatures favored the photoreduction process. As for the recycle tests of the best photocatalyst, it was discovered a significant efficiency loss between cycles, which was linked to the occlusion of active sites through the formation of chrome-based species on the surface of the photocatalyst.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 2","pages":"568 - 581"},"PeriodicalIF":2.3,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-18DOI: 10.1007/s10971-024-06520-8
Huda F. Khalil, Shams A. M. Issa, Sherif G. Elsharkawy, Roya Boudaghi Malidarreh, Sara Gad, Ali Badawi, Fatma Fakhry, Hesham M. H. Zakaly
In this investigation, the incorporation of Gd3+ ions into ZMF-spinel ferrites through the citrate sol-gel auto-combustion method significantly modified their structural, magneto-optical, and gamma-ray attenuation properties. Doping levels were varied across samples labeled ZMF0 to ZMF4 with Gd3+ concentrations ranging from 0.000 to 0.100. Advanced characterization techniques such as XRD, SEM, TEM, FT-IR, Raman spectroscopy, and XPS, alongside UV-vis spectroscopy and VSM measurements, highlighted the profound impact of Gd3+ doping. Notably, the incorporation of Gd3+ led to nano-sized cubic structures with an optimized crystallite size of 19.82 nm in the ZMF4 sample, and a notable reduction in the band gap from 3.21 eV to 2.99 eV was observed, indicative of enhanced electronic properties. Magnetic analysis revealed a transition towards superparamagnetic behavior, with a decrease in coercivity and squareness ratios, suggesting applications in areas such as data storage and optical waveguides. Furthermore, the study leveraged FLUKA Monte Carlo simulations to assess the gamma-ray shielding efficiency of these materials. It was found that increasing Gd3+ concentration or sample thickness markedly improved radiation attenuation, highlighting the material’s enhanced shielding capabilities against a range of photon energies. The most significant findings included the optimized sample (ZMF4) displaying superior magneto-optical characteristics and outstanding gamma-ray shielding performance, especially at higher Gd3+ levels. This investigation underlines the critical role of Gd3+ doping in advancing the functional properties of ZMF-spinel ferrites for technological and radiation protection applications, showcasing the potential of tailored nanomaterials in addressing complex challenges in material science.
{"title":"Advancing ZMF-spinel ferrites with Gd3+ doping: structural, magneto-optical enhancements, and superior gamma-ray shielding for high-tech applications","authors":"Huda F. Khalil, Shams A. M. Issa, Sherif G. Elsharkawy, Roya Boudaghi Malidarreh, Sara Gad, Ali Badawi, Fatma Fakhry, Hesham M. H. Zakaly","doi":"10.1007/s10971-024-06520-8","DOIUrl":"10.1007/s10971-024-06520-8","url":null,"abstract":"<div><p>In this investigation, the incorporation of Gd<sup>3+</sup> ions into ZMF-spinel ferrites through the citrate sol-gel auto-combustion method significantly modified their structural, magneto-optical, and gamma-ray attenuation properties. Doping levels were varied across samples labeled ZMF0 to ZMF4 with Gd3+ concentrations ranging from 0.000 to 0.100. Advanced characterization techniques such as XRD, SEM, TEM, FT-IR, Raman spectroscopy, and XPS, alongside UV-vis spectroscopy and VSM measurements, highlighted the profound impact of Gd<sup>3+</sup> doping. Notably, the incorporation of Gd<sup>3+</sup> led to nano-sized cubic structures with an optimized crystallite size of 19.82 nm in the ZMF4 sample, and a notable reduction in the band gap from 3.21 eV to 2.99 eV was observed, indicative of enhanced electronic properties. Magnetic analysis revealed a transition towards superparamagnetic behavior, with a decrease in coercivity and squareness ratios, suggesting applications in areas such as data storage and optical waveguides. Furthermore, the study leveraged FLUKA Monte Carlo simulations to assess the gamma-ray shielding efficiency of these materials. It was found that increasing Gd<sup>3+</sup> concentration or sample thickness markedly improved radiation attenuation, highlighting the material’s enhanced shielding capabilities against a range of photon energies. The most significant findings included the optimized sample (ZMF4) displaying superior magneto-optical characteristics and outstanding gamma-ray shielding performance, especially at higher Gd<sup>3+</sup> levels. This investigation underlines the critical role of Gd3+ doping in advancing the functional properties of ZMF-spinel ferrites for technological and radiation protection applications, showcasing the potential of tailored nanomaterials in addressing complex challenges in material science.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 3","pages":"898 - 921"},"PeriodicalIF":2.3,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fused silica glass is prepared by dispersing silica nanoparticles (SiNPs) through the hydroxyethyl methacrylate (HEMA). The dispersion of SiNPs was characterized using transmission electron microscopy and small angle X-ray scattering. The rheological properties and functional groups of SiNP slurries were analyzed utilizing a rotational rheometer and fourier transform infrared spectroscopy. The sintering quality of the fused silica glass was characterized through scanning electron microscopy and X-ray diffraction. The research results show that HEMA adsorbs on the surface of SiNP through hydrogen bonding to form a solvation layer of a certain thickness, thereby hindering the agglomeration of SiNPs. The SiNP slurry system exhibits bi-fractal properties. The viscosity and shear stress of the SiNP slurry initially decrease and then increase with increasing HEMA content. Achieving a homogeneous dispersion of SiNPs in the slurry is essential for sintering high-quality silica glass. The internal voids of agglomerates are the origin of crack formation.
Graphical Abstract
通过甲基丙烯酸羟乙酯（HEMA）分散二氧化硅纳米颗粒（SiNPs），制备出熔融二氧化硅玻璃。利用透射电子显微镜和小角 X 射线散射对 SiNPs 的分散进行了表征。利用旋转流变仪和傅里叶变换红外光谱分析了 SiNP 浆料的流变特性和官能团。通过扫描电子显微镜和 X 射线衍射对熔融石英玻璃的烧结质量进行了表征。研究结果表明，HEMA 通过氢键吸附在 SiNP 表面，形成一定厚度的溶胶层，从而阻碍了 SiNP 的团聚。SiNP 浆料体系表现出双分形特性。随着 HEMA 含量的增加，SiNP 浆料的粘度和剪切应力先降低后升高。在浆料中实现 SiNPs 的均匀分散对于烧结高质量的硅玻璃至关重要。团聚体的内部空隙是裂纹形成的根源。
{"title":"The crucial role of hydroxyethyl methacrylate in the sintering of fused silica glass using ultraviolet-cured silica nanoparticle slurries: dispersing nanoparticles","authors":"Youwang Hu, Guilin Wang, Qinglong Zhang, Xiaoyan Sun, Haikuan Chen","doi":"10.1007/s10971-024-06540-4","DOIUrl":"10.1007/s10971-024-06540-4","url":null,"abstract":"<div><p>Fused silica glass is prepared by dispersing silica nanoparticles (SiNPs) through the hydroxyethyl methacrylate (HEMA). The dispersion of SiNPs was characterized using transmission electron microscopy and small angle X-ray scattering. The rheological properties and functional groups of SiNP slurries were analyzed utilizing a rotational rheometer and fourier transform infrared spectroscopy. The sintering quality of the fused silica glass was characterized through scanning electron microscopy and X-ray diffraction. The research results show that HEMA adsorbs on the surface of SiNP through hydrogen bonding to form a solvation layer of a certain thickness, thereby hindering the agglomeration of SiNPs. The SiNP slurry system exhibits bi-fractal properties. The viscosity and shear stress of the SiNP slurry initially decrease and then increase with increasing HEMA content. Achieving a homogeneous dispersion of SiNPs in the slurry is essential for sintering high-quality silica glass. The internal voids of agglomerates are the origin of crack formation.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 2","pages":"553 - 567"},"PeriodicalIF":2.3,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1007/s10971-024-06546-y
Uzma Imtiyaz, Mushtaq Ahmad Rather
This research paper analyses the adsorbent properties of a unique biomass i.e. horse chestnut shell (Aesculus hippocastanum L) activated carbon synthesized by chemical activation of KOH produced under optimized carbonization conditions for Fe3+. Research was done to look into the characteristics of the made activated carbon and its systematic effects of process parameters. Characterizations like SEM, BET, FTIR, XRD, TGA, EDX, proximate and ultimate analysis, calorific value was performed. Also effect of process parameters like initial Fe3+ ion content, contact time, dosage and temperature of system was studied for mechanism of adsorption at pH (6) of Fe3+ in an aqueous solution. Data on equilibrium and kinetic isotherms from experiments were examined, for kinetics pseudo 1st order reaction, pseudo 2nd order reaction and intraparticle diffusion has been utilised. System was fairly fitted by pseudo-2nd-order reaction. Adsorption isotherms such as Halsey, Harkin Jura, Temkin, Freundlich, and Langmuir and Dubinin Radushkevich were used and Langmuir adsorption isotherm turned out best suitable match as R2 value was found out to be 0.99. The maximum Fe3+ adsorbing ability of the HCAC4 was 138.88 mg/g at 25 °C. Thermodynamical evaluation concluded the process to be spontaneous and heat-releasing.
{"title":"Batch adsorption of Fe3+ ions from aqueous solutions using activated carbon derived from Horse Chestnut Shells found in Northwestern Himalayas: Equilibrium, kinetic and thermodynamic studies","authors":"Uzma Imtiyaz, Mushtaq Ahmad Rather","doi":"10.1007/s10971-024-06546-y","DOIUrl":"10.1007/s10971-024-06546-y","url":null,"abstract":"<div><p>This research paper analyses the adsorbent properties of a unique biomass i.e. horse chestnut shell (<i>Aesculus hippocastanum L</i>) activated carbon synthesized by chemical activation of KOH produced under optimized carbonization conditions for Fe<sup>3+</sup>. Research was done to look into the characteristics of the made activated carbon and its systematic effects of process parameters. Characterizations like SEM, BET, FTIR, XRD, TGA, EDX, proximate and ultimate analysis, calorific value was performed. Also effect of process parameters like initial Fe<sup>3+</sup> ion content, contact time, dosage and temperature of system was studied for mechanism of adsorption at pH (6) of Fe<sup>3+</sup> in an aqueous solution. Data on equilibrium and kinetic isotherms from experiments were examined, for kinetics pseudo 1st order reaction, pseudo 2nd order reaction and intraparticle diffusion has been utilised. System was fairly fitted by pseudo-2nd-order reaction. Adsorption isotherms such as Halsey, Harkin Jura, Temkin, Freundlich, and Langmuir and Dubinin Radushkevich were used and Langmuir adsorption isotherm turned out best suitable match as R<sup>2</sup> value was found out to be 0.99. The maximum Fe<sup>3+</sup> adsorbing ability of the HCAC4 was 138.88 mg/g at 25 °C. Thermodynamical evaluation concluded the process to be spontaneous and heat-releasing.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 2","pages":"533 - 552"},"PeriodicalIF":2.3,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-15DOI: 10.1007/s10971-024-06521-7
Sumia Rubab, Sarah A. Alsalhi, A. Dahshan, Muhammad Aslam, Khursheed Ahmad, Albandari.W. Alrowaily
Developing effective and durable electrocatalysts for long-term energy conversion technologies is still an ongoing problem for researchers. For this purpose, perovskite oxides have attracted significant interest as effective electrocatalysts for oxygen evolution reactions (OER) in response to their highly adjustable catalytic and electrical properties associated with their compositions. This study presents a novel hydrothermal approach to fabricate SrSnO3/rGO composite in order to accelerate the four electron transfer mechanisms. Moreover, the physical analyses show that cubic-shaped SrSnO3 are irregularly dispersed in the form of spherical on the nanosheets of rGO. Compared with pristine, the BET study shows that composite exhibits a greater surface area (59 m2 g−1). To evaluate the catalytic kinetics, conductivity and stability, the electrochemical evaluation of the electrode material (SrSnO3/rGO) was performed in alkaline media with Ni foam (NF) as substrate. The exceptional electrocatalytic performance of the material in the OER could be associated with its unique structure, many active sites, and favorable conductivity. This performance is characterized by fast reaction rates, as indicated by a minimal Tafel constant (33 mV dec−1) along with reduced overpotential (199 mV) at 10 mA cm−2. Moreover, the chronoamperometry (CA) investigation of the SrSnO3/rGO composite indicates 35 h of long-term stability. This study presents a viable approach for producing high-performing perovskite composites for effective OER electrocatalysis.
Graphical Abstract
为长期能源转换技术开发有效、耐用的电催化剂仍然是研究人员面临的一个持续问题。为此，过氧化物氧化物作为氧进化反应（OER）的有效电催化剂引起了人们的极大兴趣，因为它们的催化和电特性与其组成相关，具有很强的可调性。本研究介绍了一种新型水热法制造 SrSnO3/rGO 复合材料，以加速四种电子转移机制。此外，物理分析表明，立方体 SrSnO3 以球形不规则地分散在 rGO 纳米片上。BET 研究表明，与原始材料相比，复合材料具有更大的比表面积（59 m2 g-1）。为了评估催化动力学、电导率和稳定性，以泡沫镍（NF）为基底，在碱性介质中对电极材料（SrSnO3/rGO）进行了电化学评估。该材料在 OER 中优异的电催化性能与其独特的结构、众多的活性位点和良好的导电性有关。这种性能的特点是反应速度快，在 10 mA cm-2 的条件下，塔菲尔常数（33 mV dec-1）最小，过电位（199 mV）降低。此外，对 SrSnO3/rGO 复合材料进行的时变测量（CA）研究表明，该材料具有 35 小时的长期稳定性。这项研究为生产高性能的包晶石复合材料以实现有效的 OER 电催化提供了一种可行的方法。
{"title":"Fabrication of SrSnO3/rGO composite via hydrothermal technique as robust electrocatalyst for OER process","authors":"Sumia Rubab, Sarah A. Alsalhi, A. Dahshan, Muhammad Aslam, Khursheed Ahmad, Albandari.W. Alrowaily","doi":"10.1007/s10971-024-06521-7","DOIUrl":"10.1007/s10971-024-06521-7","url":null,"abstract":"<div><p>Developing effective and durable electrocatalysts for long-term energy conversion technologies is still an ongoing problem for researchers. For this purpose, perovskite oxides have attracted significant interest as effective electrocatalysts for oxygen evolution reactions (OER) in response to their highly adjustable catalytic and electrical properties associated with their compositions. This study presents a novel hydrothermal approach to fabricate SrSnO<sub>3</sub>/rGO composite in order to accelerate the four electron transfer mechanisms. Moreover, the physical analyses show that cubic-shaped SrSnO<sub>3</sub> are irregularly dispersed in the form of spherical on the nanosheets of rGO. Compared with pristine, the BET study shows that composite exhibits a greater surface area (59 m<sup>2</sup> g<sup>−1</sup>). To evaluate the catalytic kinetics, conductivity and stability, the electrochemical evaluation of the electrode material (SrSnO<sub>3</sub>/rGO) was performed in alkaline media with Ni foam (NF) as substrate. The exceptional electrocatalytic performance of the material in the OER could be associated with its unique structure, many active sites, and favorable conductivity. This performance is characterized by fast reaction rates, as indicated by a minimal Tafel constant (33 mV dec<sup>−1</sup>) along with reduced overpotential (199 mV) at 10 mA cm<sup>−2</sup>. Moreover, the chronoamperometry (CA) investigation of the SrSnO<sub>3</sub>/rGO composite indicates 35 h of long-term stability. This study presents a viable approach for producing high-performing perovskite composites for effective OER electrocatalysis.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 3","pages":"885 - 897"},"PeriodicalIF":2.3,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-14DOI: 10.1007/s10971-024-06548-w
Vadim G. Kessler
Sol-Gel synthesis of metal oxides constitutes a tremendously exciting domain of inorganic chemistry, where molecular and supramolecular science meet the physical chemistry and materials science. Structure and reactivity, especially surface complexation of biologically important molecules on the surface of metal oxide nanoparticles can efficiently be traced through structural studies of metal oxo-paperbags—the product of partial hydrolysis of alkoxide precursors. Paperbag is a recently proposed term to denote oligonuclear complexes not featuring intrinsic metal-metal bonding and thus not qualified to be called “clusters”. Another important insight, provided recently by the studies of heterometallic species, is dealing with visualization of bonding modes of single atom catalysts on metal oxide substrates and reveals possible coordination environments of heteroatoms on doping. The studies of large paperbag aggregates can contribute to understanding of factors influencing the bandgap and photocatalytic activity of related oxides. The use of these species directly as photo or electro catalysts is rather debatable, however, in the view of high reactivity of these alkoxide intermediates, easily transforming them into metal oxide nanoparticles on hydrolysis or thermolysis.
{"title":"Metal alkoxides as models for metal oxides—the concept revisited","authors":"Vadim G. Kessler","doi":"10.1007/s10971-024-06548-w","DOIUrl":"10.1007/s10971-024-06548-w","url":null,"abstract":"<div><p>Sol-Gel synthesis of metal oxides constitutes a tremendously exciting domain of inorganic chemistry, where molecular and supramolecular science meet the physical chemistry and materials science. Structure and reactivity, especially surface complexation of biologically important molecules on the surface of metal oxide nanoparticles can efficiently be traced through structural studies of metal oxo-paperbags—the product of partial hydrolysis of alkoxide precursors. Paperbag is a recently proposed term to denote oligonuclear complexes not featuring intrinsic metal-metal bonding and thus not qualified to be called “clusters”. Another important insight, provided recently by the studies of heterometallic species, is dealing with visualization of bonding modes of single atom catalysts on metal oxide substrates and reveals possible coordination environments of heteroatoms on doping. The studies of large paperbag aggregates can contribute to understanding of factors influencing the bandgap and photocatalytic activity of related oxides. The use of these species directly as photo or electro catalysts is rather debatable, however, in the view of high reactivity of these alkoxide intermediates, easily transforming them into metal oxide nanoparticles on hydrolysis or thermolysis.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 2","pages":"502 - 511"},"PeriodicalIF":2.3,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10971-024-06548-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-14DOI: 10.1007/s10971-024-06371-3
Jie Chen, Jianxing Ma, Charles M. Black, Yuchen Shao, Jincheng Lei, Hai Xiao, Fei Peng
Silica microspheres have been demonstrated as the optical micro-cavity for laser generation based on whispering-gallery modes (WGM). They can achieve a high-quality factor (Q) within a tiny volume. Traditionally, complex processes are needed to process a coating containing photoluminescent elements, with enough thickness and uniformity, for laser generation. We developed a novel sol-gel fabrication method of Er3+/Yb3+doped silica microspheres with a homogeneous doping concentration over the entire microsphere volume. The sol-gel precursors were doped with 1–2 mol% Er3+ and/or Yb3+. The viscosity of the precursor was controlled at around 4000 cP, and gel fibers can be conveniently drawn from the precursor. After firing at 1000 °C for 1 h, transparent fibers with diameters of 40–180 µm were obtained. The fiber tips were quickly melted into microspheres using a CO2 laser. The diameters of microspheres were determined by the fiber diameter and laser parameters, such as laser power and irradiation time duration. Typically, the microspheres had diameters between 90 to 160 µm. The emission spectrum under 357 nm and 527 nm excitation showed characteristic Er3+ emission peaks, that match the literature well. The UV-VIS spectra confirm the photoluminescence results and showed both Er3+ and Yb3+ characteristic absorptions. The optical behaviors of the microspheres indicate that the Er3+ and Yb3+ were well dispersed in the silica matrix and the microspheres had typical optical activities of Er3+/Yb3+ glasses.
{"title":"Fabrication of sol-gel derived homogeneously doped Er3+/Yb3+:SiO2 microspheres using laser melting","authors":"Jie Chen, Jianxing Ma, Charles M. Black, Yuchen Shao, Jincheng Lei, Hai Xiao, Fei Peng","doi":"10.1007/s10971-024-06371-3","DOIUrl":"10.1007/s10971-024-06371-3","url":null,"abstract":"<div><p>Silica microspheres have been demonstrated as the optical micro-cavity for laser generation based on whispering-gallery modes (WGM). They can achieve a high-quality factor (Q) within a tiny volume. Traditionally, complex processes are needed to process a coating containing photoluminescent elements, with enough thickness and uniformity, for laser generation. We developed a novel sol-gel fabrication method of Er<sup>3+</sup>/Yb<sup>3+</sup>doped silica microspheres with a homogeneous doping concentration over the entire microsphere volume. The sol-gel precursors were doped with 1–2 mol% Er<sup>3+</sup> and/or Yb<sup>3+</sup>. The viscosity of the precursor was controlled at around 4000 cP, and gel fibers can be conveniently drawn from the precursor. After firing at 1000 °C for 1 h, transparent fibers with diameters of 40–180 µm were obtained. The fiber tips were quickly melted into microspheres using a CO<sub>2</sub> laser. The diameters of microspheres were determined by the fiber diameter and laser parameters, such as laser power and irradiation time duration. Typically, the microspheres had diameters between 90 to 160 µm. The emission spectrum under 357 nm and 527 nm excitation showed characteristic Er<sup>3+</sup> emission peaks, that match the literature well. The UV-VIS spectra confirm the photoluminescence results and showed both Er<sup>3+</sup> and Yb<sup>3+</sup> characteristic absorptions. The optical behaviors of the microspheres indicate that the Er<sup>3+</sup> and Yb<sup>3+</sup> were well dispersed in the silica matrix and the microspheres had typical optical activities of Er<sup>3+</sup>/Yb<sup>3+</sup> glasses.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":664,"journal":{"name":"Journal of Sol-Gel Science and Technology","volume":"112 2","pages":"494 - 501"},"PeriodicalIF":2.3,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10971-024-06371-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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