Pub Date : 2024-08-03DOI: 10.1016/j.apt.2024.104610
Bandgap engineering has been effectively used to reduce the shallow-trap defects (e.g. antisite defects), but there are still rare reports on the removal of deep-trap defects (e.g. oxygen defects). In this work, our proposed strategy of In3+ substitution for Lu3+ via the formation of continuous (Lu,In)2O3 solid solutions can be used to widely tailored the bandgap energy. These solid solutions prepared from the chemical co-precipitation route presented the rounded morphology and their particle sizes increased at a higher In3+ content. The (Lu,In)2O3:Tm phosphor powders exhibited characteristic Tm3+ emissions arising from its intra‐4f12 multi‐transitions upon UV excitation into strong broad charge transfer bands. The luminescence intensity reached the highest level at 15 at.% In3+ concentration. The In3+ incorporation was found to red-shift the charge transfer bands and shortened the florescence lifetimes. The luminescence quenching was dominated by exchange interaction while the theoretical and experimental quenching concentration of Tm3+ coincided well with each other (both ∼1 at.%). The trap depth in the In3+ free Lu2O3:Tm phosphor was determined to be ∼0.61 eV and these electron traps could be almost fully buried at the In3+ concentration above 5 at.%. Both the (Lu0.99Tm0.01)2O3 and (Lu0.84In0.15Tm0.01)2O3 phosphors exhibited good thermal stability with high thermal-quenching activation energies (∼0.45 eV for the former and ∼0.39 eV for the latter). However, the (Lu0.99Tm0.01)2O3 phosphor presented abnormal thermal quenching effect.
带隙工程已被有效地用于减少浅阱缺陷(.反位错缺陷),但关于消除深阱缺陷(.氧缺陷)的报道仍然很少。在这项工作中,我们提出了通过形成连续的(Lu,In)O 固溶体用 In 替代 Lu 的策略,可用于广泛调整带隙能。这些通过化学共沉淀路线制备的固溶体呈现出圆形的形态,并且当 In 含量越高时,其粒径也越大。(Lu,In)O:Tm荧光粉在紫外光激发下会发生4内多跃迁,形成强宽的电荷转移带,从而产生特征性的Tm发射。当 In 浓度为 15%时,发光强度达到最高水平。铟的掺入使电荷转移带发生红移,并缩短了荧光寿命。发光淬灭主要是由交换相互作用引起的,而 Tm 的理论淬灭浓度和实验淬灭浓度非常吻合(均为 1 at.%)。无 In 的 LuO:Tm 荧光粉中的陷阱深度被测定为 ∼0.61 eV,当 In 浓度超过 5 at.% 时,这些电子陷阱几乎可以完全埋藏。(LuTm)O和(LuInTm)O荧光粉都具有良好的热稳定性,热淬灭活化能较高(前者为0.45 eV,后者为0.39 eV)。然而,(LuTm)O 荧光粉却表现出异常的热淬火效应。
{"title":"Removal of deep traps in Lu2O3:Tm phosphors via formation of continuous solid solutions with In2O3 enabling widely tailorable bandgap energy","authors":"","doi":"10.1016/j.apt.2024.104610","DOIUrl":"10.1016/j.apt.2024.104610","url":null,"abstract":"<div><p>Bandgap engineering has been effectively used to reduce the shallow-trap defects (<em>e</em>.<em>g</em>. antisite defects), but there are still rare reports on the removal of deep-trap defects (<em>e</em>.<em>g</em>. oxygen defects). In this work, our proposed strategy of In<sup>3+</sup> substitution for Lu<sup>3+</sup> via the formation of continuous (Lu,In)<sub>2</sub>O<sub>3</sub> solid solutions can be used to widely tailored the bandgap energy. These solid solutions prepared from the chemical co-precipitation route presented the rounded morphology and their particle sizes increased at a higher In<sup>3+</sup> content. The (Lu,In)<sub>2</sub>O<sub>3</sub>:Tm phosphor powders exhibited characteristic Tm<sup>3+</sup> emissions arising from its intra‐4<em>f</em><sup>12</sup> multi‐transitions upon UV excitation into strong broad charge transfer bands. The luminescence intensity reached the highest level at 15 at.% In<sup>3+</sup> concentration. The In<sup>3+</sup> incorporation was found to red-shift the charge transfer bands and shortened the florescence lifetimes. The luminescence quenching was dominated by exchange interaction while the theoretical and experimental quenching concentration of Tm<sup>3+</sup> coincided well with each other (both ∼1 at.%). The trap depth in the In<sup>3+</sup> free Lu<sub>2</sub>O<sub>3</sub>:Tm phosphor was determined to be ∼0.61 eV and these electron traps could be almost fully buried at the In<sup>3+</sup> concentration above 5 at.%. Both the (Lu<sub>0.99</sub>Tm<sub>0.01</sub>)<sub>2</sub>O<sub>3</sub> and (Lu<sub>0.84</sub>In<sub>0.15</sub>Tm<sub>0.01</sub>)<sub>2</sub>O<sub>3</sub> phosphors exhibited good thermal stability with high thermal-quenching activation energies (∼0.45 eV for the former and ∼0.39 eV for the latter). However, the (Lu<sub>0.99</sub>Tm<sub>0.01</sub>)<sub>2</sub>O<sub>3</sub> phosphor presented abnormal thermal quenching effect.</p></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141945503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-08-02DOI: 10.1016/j.apt.2024.104607
Depressant starch (NS) was generally used in hematite flotation, while the adsorption mechanism of the macromolecular polymer onto mineral surfaces remained in question. In this study, novel detection approaches and computational chemistry methods were introduced to update the widely-accepted acid-base interaction theory. Microflotation tests confirm that the hematite flotation recovery was easily depressed by NS under the acid or alkaline conditions rather than the neutral condition. Zeta potential measurement shows that NS could change the zeta potential of hematite, while the shift amplitude ranked as alkaline > acid > neutral, indicating the most suitable pH range is the alkaline condition. XPS analysis reveals that NS could chemisorbed onto Fe atoms of hematite surface via C-O groups in the whole studied pH range. It was further verified using AFM tests, in which the NS has a stronger interaction force under the alkaline environment. MDS further indicates that the interaction energy between NS and the (0 0 1) hematite surface was three times greater than others under alkaline conditions. In general, the interaction force at the interface between the hematite surface and NS was a strong chemical adsorption at the alkaline conditions while there was weak chemisorption and hydrogen bonding under the neutral or acidic conditions.
{"title":"A novel interaction theory for the starch adsorption onto hematite surface","authors":"","doi":"10.1016/j.apt.2024.104607","DOIUrl":"10.1016/j.apt.2024.104607","url":null,"abstract":"<div><p>Depressant starch (NS) was generally used in hematite flotation, while the adsorption mechanism of the macromolecular polymer onto mineral surfaces remained in question. In this study, novel detection approaches and computational chemistry methods were introduced to update the widely-accepted acid-base interaction theory. Microflotation tests confirm that the hematite flotation recovery was easily depressed by NS under the acid or alkaline conditions rather than the neutral condition. Zeta potential measurement shows that NS could change the zeta potential of hematite, while the shift amplitude ranked as alkaline > acid > neutral, indicating the most suitable pH range is the alkaline condition. XPS analysis reveals that NS could chemisorbed onto Fe atoms of hematite surface via C-O groups in the whole studied pH range. It was further verified using AFM tests, in which the NS has a stronger interaction force under the alkaline environment. MDS further indicates that the interaction energy between NS and the (0<!--> <!-->0<!--> <!-->1) hematite surface was three times greater than others under alkaline conditions. In general, the interaction force at the interface between the hematite surface and NS was a strong chemical adsorption at the alkaline conditions while there was weak chemisorption and hydrogen bonding under the neutral or acidic conditions.</p></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141951479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-30DOI: 10.1016/j.apt.2024.104603
To improve vertical mill performance, a vertical stirred mill is used as the research object. Firstly, an electromechanical multi-body dynamic model (EMBD) of the vertical stirred mill is established, followed by the establishment of a discrete element method (DEM) analysis model of the grinding media, and then the DEM-EMBD coupling model is formed. The feasibility of the DEM-EMBD coupling model is verified through experiments. On this basis, the stress distribution state of the helical agitator is analysed based on the coupling method of the discrete element method and finite element method (DEM-EMBD-FEM). The DEM-EMBD coupling model can better reflect the dynamic characteristics of the vertical stirred mill by comparing it with the DEM model and the coupling method of discrete element method and computational fluid dynamics (DEM-CFD) respectively. Finally, the effects of vertical stirred mill structural parameters, operating parameters and grinding media size on mill performance are investigated by the DEM-EMBD and DEM-EMBD-FEM coupling models. The approach then provides insights into the structural design of vertical stirred mills, motor selection, and the welding process between the helical blades and screw.
{"title":"Performance analysis of vertical stirred mill based on multi-coupling method","authors":"","doi":"10.1016/j.apt.2024.104603","DOIUrl":"10.1016/j.apt.2024.104603","url":null,"abstract":"<div><p>To improve vertical mill performance, a vertical stirred mill is used as the research object. Firstly, an electromechanical multi-body dynamic model (EMBD) of the vertical stirred mill is established, followed by the establishment of a discrete element method (DEM) analysis model of the grinding media, and then the DEM-EMBD coupling model is formed. The feasibility of the DEM-EMBD coupling model is verified through experiments. On this basis, the stress distribution state of the helical agitator is analysed based on the coupling method of the discrete element method and finite element method (DEM-EMBD-FEM). The DEM-EMBD coupling model can better reflect the dynamic characteristics of the vertical stirred mill by comparing it with the DEM model and the coupling method of discrete element method and computational fluid dynamics (DEM-CFD) respectively. Finally, the effects of vertical stirred mill structural parameters, operating parameters and grinding media size on mill performance are investigated by the DEM-EMBD and DEM-EMBD-FEM coupling models. The approach then provides insights into the structural design of vertical stirred mills, motor selection, and the welding process between the helical blades and screw.</p></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141950282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-30DOI: 10.1016/j.apt.2024.104604
Addressing the persistent challenge of separating smithsonite from calcite using flotation method, this study explores the impact of carboxymethyl chitosan (CMCS) on selective separation using sodium oleate (NaOL) assisted flotation. Results indicated a substantial reduction in calcite recovery to 2.25 % with the addition of 40 mg/L CMCS at pH 9, while recovery of smithsonite remained essentially unchanged at 94.78 %. Moreover, we found that using CMCS as the depressant can effectively separate smithsonite from calcite, based on the flotation testing results with artificially mixed minerals. Contact angle tests results showed that CMCS can significantly lower the surface hydrophobicity of calcite without any negative effect on that of smithsonite when using NaOL as a collector. TOC, FTIR, AFM, and ToF-SIMS analyses demonstrated stronger adsorption of CMCS on the surface of calcite compared to smithsonite. XPS data, solution chemical analysis and DFT revealed interaction between –COO- in CMCS with Ca sites on the surface of calcite because of the electrostatic adsorption and chemical adsorption, forming −COOCa. It leaded to shielding effects on the NaOL adsorption stemming, which makes NaOL more adsorbed on smithsonite surface.
{"title":"Influence of carboxymethyl chitosan on selective flotation separation of smithsonite from calcite with sodium oleate","authors":"","doi":"10.1016/j.apt.2024.104604","DOIUrl":"10.1016/j.apt.2024.104604","url":null,"abstract":"<div><p>Addressing the persistent challenge of separating smithsonite from calcite using flotation method, this study explores the impact of carboxymethyl chitosan (CMCS) on selective separation using sodium oleate (NaOL) assisted flotation. Results indicated a substantial reduction in calcite recovery to 2.25 % with the addition of 40 mg/L CMCS at pH 9, while recovery of smithsonite remained essentially unchanged at 94.78 %. Moreover, we found that using CMCS as the depressant can effectively separate smithsonite from calcite, based on the flotation testing results with artificially mixed minerals. Contact angle tests results showed that CMCS can significantly lower the surface hydrophobicity of calcite without any negative effect on that of smithsonite when using NaOL as a collector. TOC, FTIR, AFM, and ToF-SIMS analyses demonstrated stronger adsorption of CMCS on the surface of calcite compared to smithsonite. XPS data, solution chemical analysis and DFT revealed interaction between –COO- in CMCS with Ca sites on the surface of calcite because of the electrostatic adsorption and chemical adsorption, forming −COOCa. It leaded to shielding effects on the NaOL adsorption stemming, which makes NaOL more adsorbed on smithsonite surface.</p></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141950284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-30DOI: 10.1016/j.apt.2024.104606
Calcite is a common gangue mineral in tin ore, which seriously affects the flotation of fine-grained cassiterite. The enhanced flotation separation of fine-grained cassiterite and calcite with cetylpyridine bromide (CPB) as a dispersant were investigated in the study. The CPB significantly improved the flotation separation efficiency of fine-grained cassiterite and calcite, and it exhibited an excellent dispersion effect and relieved the coating phenomenon of calcite particles on the surface of cassiterite particles. The CPB changed the surface potential of cassiterite from negative value to positive value when the pH was in the range of 3.4–11.5. However, regardless of treatment with CPB, the surface potential of calcite was positive when the pH was below 11.5. The O on the surface of cassiterite reacted with CPB, promoting the chemical adsorption of CPB on the surface of cassiterite. There was weak physical adsorption between CPB and calcite. The covering between cassiterite and calcite without CPB was mainly dependent on van der Waals interaction energy and electrostatic interaction energy. When CPB was in the presence, cassiterite and calcite were repelled by the hydrophobic interaction energy and electrostatic interaction energy.
{"title":"Enhancing flotation separation of fine-grained cassiterite and calcite with cetylpyridine bromide as a dispersant","authors":"","doi":"10.1016/j.apt.2024.104606","DOIUrl":"10.1016/j.apt.2024.104606","url":null,"abstract":"<div><p>Calcite is a common gangue mineral in tin ore, which seriously affects the flotation of fine-grained cassiterite. The enhanced flotation separation of fine-grained cassiterite and calcite with cetylpyridine bromide (CPB) as a dispersant were investigated in the study. The CPB significantly improved the flotation separation efficiency of fine-grained cassiterite and calcite, and it exhibited an excellent dispersion effect and relieved the coating phenomenon of calcite particles on the surface of cassiterite particles. The CPB changed the surface potential of cassiterite from negative value to positive value when the pH was in the range of 3.4–11.5. However, regardless of treatment with CPB, the surface potential of calcite was positive when the pH was below 11.5. The O on the surface of cassiterite reacted with CPB, promoting the chemical adsorption of CPB on the surface of cassiterite. There was weak physical adsorption between CPB and calcite. The covering between cassiterite and calcite without CPB was mainly dependent on van der Waals interaction energy and electrostatic interaction energy. When CPB was in the presence, cassiterite and calcite were repelled by the hydrophobic interaction energy and electrostatic interaction energy.</p></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141950283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-30DOI: 10.1016/j.apt.2024.104577
Computation of blood flow containing ferrofluid would be useful for analysis of drug carrier motion for cancer therapy. A thorough understanding nanoparticles behavior is challenging and needs to be addressed by developing sophisticated theoretical methods. A hybrid modeling for analysis of blood motion containing ferrofluid was implemented via mechanistic modeling combined with artificial intelligence. The system of analysis also considered external magnetic force for control of nanoparticles motion in the blood vessel. This research focuses on the analysis of velocity field based on a dataset consisting of variables x(m), y(m), and U(m/s). The objective is to develop accurate predictive models using Gaussian Process Regression (GPR), Kernel ridge regression (KRR), and Polynomial Regression (PR). The Dragonfly Algorithm (DA) was employed for hyper-parameter optimizing. The results demonstrate the performance of these models in relation to R2 score, RMSE, and MAE. The GPR model achieves the highest score of 0.99603 in terms of R2, indicating excellent predictive accuracy. It also exhibits the lowest RMSE of 7.1443x10^-3 and MAE of 5.35436 x10^-3, suggesting minimal deviations between the expected and predicted velocity values. The PR model also has a significant performance with an R2 test score of 0.99348, RMSE of 9.1376 x10^-3, and MAE of 7.22828 x10^-3. The aforementioned results underscore the effectiveness of these models in accurately forecasting velocity based on the provided input variables.
{"title":"Development of computational model for description of magnetic drug targeting for cancer therapy: Modeling and validation","authors":"","doi":"10.1016/j.apt.2024.104577","DOIUrl":"10.1016/j.apt.2024.104577","url":null,"abstract":"<div><p>Computation of blood flow containing ferrofluid would be useful for analysis of drug carrier motion for cancer therapy. A thorough understanding nanoparticles behavior is challenging and needs to be addressed by developing sophisticated theoretical methods. A hybrid modeling for analysis of blood motion containing ferrofluid was implemented via mechanistic modeling combined with artificial intelligence. The system of analysis also considered external magnetic force for control of nanoparticles motion in the blood vessel. This research focuses on the analysis of velocity field based on a dataset consisting of variables x(m), y(m), and U(m/s). The objective is to develop accurate predictive models using Gaussian Process Regression (GPR), Kernel ridge regression (KRR), and Polynomial Regression (PR). The Dragonfly Algorithm (DA) was employed for hyper-parameter optimizing. The results demonstrate the performance of these models in relation to R<sup>2</sup> score, RMSE, and MAE. The GPR model achieves the highest score of 0.99603 in terms of R<sup>2</sup>, indicating excellent predictive accuracy. It also exhibits the lowest RMSE of 7.1443x10^-3 and MAE of 5.35436 x10^-3, suggesting minimal deviations between the expected and predicted velocity values. The PR model also has a significant performance with an R<sup>2</sup> test score of 0.99348, RMSE of 9.1376 x10^-3, and MAE of 7.22828 x10^-3. The aforementioned results underscore the effectiveness of these models in accurately forecasting velocity based on the provided input variables.</p></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141950265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-27DOI: 10.1016/j.apt.2024.104567
Due to their unique properties and suitability for a wide range of applications, nanometer-scale semiconductors such as ZnO have garnered much attention. We successfully synthesized undoped and doped ZnO (Mg/Cu/N-ZnO and Mg/Cu/N/B-ZnO) using the solid-state method and analyzed using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Raman Spectroscopy, UV − Visible Diffuse Reflectance (UV– Vis DRS), and Photoluminescence spectra (PL). The synthesized material exhibited a hexagonal structure in the presence of additional potentially doped ZnO defects, as evidenced by the XRD and Raman spectra. The scanning electron microscopy (SEM) study showed that the undoped ZnO exhibited a rod-shaped morphology with a non-uniform size distribution. In contrast, the doped ZnO particles had an almost spherical shape. The particle sizes of undoped ZnO are 91.52 nm, while doped ZnO particles are 74.92 nm for Mg/Cu/N-ZnO and 42.28 nm for Mg/Cu/N/B-ZnO. According to BET analysis, Mg/Cu/N- ZnO exhibits the highest specific surface area, measured at 803.009 m2/g. X-ray photoelectron spectroscopy verified the presence of dopants within the ZnO lattice. The UV-DRS study results showed that doping impacts the bandgap energy. The PL spectrum shows the formation of UV emission (∼400 nm) and visible emission (513–520 nm and ∼ 649 nm) peaks, indicating the inhibition of electron-hole recombination and various types of defects, including intrinsic and extrinsic defects. The photocatalytic activities of undoped ZnO and doped ZnO for methyl violet (MV) degradation were investigated using UV–vis spectroscopy after 120 min of exposure to visible light. Triple and quadruple-doped ZnO showed excellent photocatalytic ability to degrade a 93 – 95 % solution of methyl violet. The material’s stability was assessed through five cycles of the photocatalyst, and characterization data (XRD, XPS) for the catalyst utilized are also provided. Antibacterial activity increased against S. aureus and E. coli bacteria in quadruple-doped ZnO samples. The Mg/Cu/N/B-ZnO sample had the most significant antibacterial activity, with an average zone of inhibition measuring 9.85 mm for S. aureus and 11.95 mm for E. coli.
{"title":"Unlocking the photocatalytic and antibacterial properties of triple and quadruple doped ZnO nanoparticles (Mg/Cu/N-ZnO and Mg/Cu/N/B-ZnO) prepared by one pot facile solid state synthesis","authors":"","doi":"10.1016/j.apt.2024.104567","DOIUrl":"10.1016/j.apt.2024.104567","url":null,"abstract":"<div><p>Due to their unique properties and suitability for a wide range of applications, nanometer-scale semiconductors such as ZnO have garnered much attention. We successfully synthesized undoped and doped ZnO (Mg/Cu/N-ZnO and Mg/Cu/N/B-ZnO) using the solid-state method and analyzed using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Raman Spectroscopy, UV − Visible Diffuse Reflectance (UV– Vis DRS), and Photoluminescence spectra (PL). The synthesized material exhibited a hexagonal structure in the presence of additional potentially doped ZnO defects, as evidenced by the XRD and Raman spectra. The scanning electron microscopy (SEM) study showed that the undoped ZnO exhibited a rod-shaped morphology with a non-uniform size distribution. In contrast, the doped ZnO particles had an almost spherical shape. The particle sizes of undoped ZnO are 91.52 nm, while doped ZnO particles are 74.92 nm for Mg/Cu/N-ZnO and 42.28 nm for Mg/Cu/N/B-ZnO. According to BET analysis, Mg/Cu/N- ZnO exhibits the highest specific surface area, measured at 803.009 m<sup>2</sup>/g. X-ray photoelectron spectroscopy verified the presence of dopants within the ZnO lattice. The UV-DRS study results showed that doping impacts the bandgap energy. The PL spectrum shows the formation of UV emission (∼400 nm) and visible emission (513–520 nm and ∼ 649 nm) peaks, indicating the inhibition of electron-hole recombination and various types of defects, including intrinsic and extrinsic defects. The photocatalytic activities of undoped ZnO and doped ZnO for methyl violet (MV) degradation were investigated using UV–vis spectroscopy after 120 min of exposure to visible light. Triple and quadruple-doped ZnO showed excellent photocatalytic ability to degrade a 93 – 95 % solution of methyl violet. The material’s stability was assessed through five cycles of the photocatalyst, and characterization data (XRD, XPS) for the catalyst utilized are also provided. Antibacterial activity increased against <em>S. aureus</em> and <em>E. coli</em> bacteria in quadruple-doped ZnO samples. The Mg/Cu/N/B-ZnO sample had the most significant antibacterial activity, with an average zone of inhibition measuring 9.85 mm for <em>S. aureus</em> and 11.95 mm for <em>E. coli</em>.</p></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141950222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 : 2024-07-27DOI: 10.1016/j.apt.2024.104595
We developed a multi-emission fluorescence sensor based on hybridizing two different fluorescent centers, which provides a built-in correction to remove environmental effects. Eu3+ doped Gd2O3 nanoparticles were embedded in the silica hollow spheres while the fluorophore naphthalene derived molecules were covalently linked to the surface of silica to form multi-emission fluorescence sensors (Eu3+/Gd2O3@HSiO2/NCO). With a detection limit of 3.8 nM, the nanosensor offers an effective platform for reliable Cr6+ detection. The obtained accuracy is considerably lower than the maximum level of Cr6+ in drinking water permitted by the U.S. Environmental Protection Agency (EPA). The prepared Eu3+/Gd2O3@HSiO2/NCO inherited simultaneously the excellent luminescence performance of Eu3+/Gd2O3 and the fluorophore group and exhibited interesting structural and fluorescence stability in aqueous solution. A higher enhancement of fluorescence emission stemming from an intrinsic structure of Eu3+/Gd2O3 nanoparticles was observed by adding Cr6+ ions as opposed to naphthalene molecules. There was a good linear relationship between the sum of fluorescence intensity changes (ΔI330 + ΔI610) and the Cr6+ concentration in the range of 0.1–1.0 ppm. The nanosensor fabricated by this method showed good reversibility, enabling the rapid detection of Cr6+ in real water samples. As a result of this groundbreaking study, we are able to develop an idea for building a multifunctional fluorescent probe, with potential applications in biotechnology, food analysis, and environmental analysis.
{"title":"A selective multi-emission chemiluminescence system using hollow Eu3+/Gd2O3@SiO2 spheres modified by naphthalene derived molecules for the quantification of Cr6+ ions","authors":"","doi":"10.1016/j.apt.2024.104595","DOIUrl":"10.1016/j.apt.2024.104595","url":null,"abstract":"<div><p>We developed a multi-emission fluorescence sensor based on hybridizing two different fluorescent centers, which provides a built-in correction to remove environmental effects. Eu<sup>3+</sup> doped Gd<sub>2</sub>O<sub>3</sub> nanoparticles were embedded in the silica hollow spheres while the fluorophore naphthalene derived molecules were covalently linked to the surface of silica to form multi-emission fluorescence sensors (Eu<sup>3+</sup>/Gd<sub>2</sub>O<sub>3</sub>@HSiO<sub>2</sub>/NCO). With a detection limit of 3.8 nM, the nanosensor offers an effective platform for reliable Cr<sup>6+</sup> detection. The obtained accuracy is considerably lower than the maximum level of Cr<sup>6+</sup> in drinking water permitted by the U.S. Environmental Protection Agency (EPA). The prepared Eu<sup>3+</sup>/Gd<sub>2</sub>O<sub>3</sub>@HSiO<sub>2</sub>/NCO inherited simultaneously the excellent luminescence performance of Eu<sup>3+</sup>/Gd<sub>2</sub>O<sub>3</sub> and the fluorophore group and exhibited interesting structural and fluorescence stability in aqueous solution. A higher enhancement of fluorescence emission stemming from an intrinsic structure of Eu<sup>3+</sup>/Gd<sub>2</sub>O<sub>3</sub> nanoparticles was observed by adding Cr<sup>6+</sup> ions as opposed to naphthalene molecules. There was a good linear relationship between the sum of fluorescence intensity changes (ΔI<sub>330</sub> + ΔI<sub>610</sub>) and the Cr<sup>6+</sup> concentration in the range of 0.1–1.0 ppm. The nanosensor fabricated by this method showed good reversibility, enabling the rapid detection of Cr<sup>6+</sup> in real water samples. As a result of this groundbreaking study, we are able to develop an idea for building a multifunctional fluorescent probe, with potential applications in biotechnology, food analysis, and environmental analysis.</p></div>","PeriodicalId":7232,"journal":{"name":"Advanced Powder Technology","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141959350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}