Many excavations contain potsherds that have suffered from different aspects of deterioration, including salt crystallization, dirt deposition, and soot. The different stains play an important role in the deterioration of archaeological pottery, such as the disappearance of the original surface and discoloration. The present study aims to evaluate some nanoparticles in an innovative poultice form to be used to clean archaeological pottery. In this study, the nanoparticles (NPs) of titanium dioxide (TiO2) and zinc oxide (ZnO) have been prepared at 5% and in the poultice form to be used for the cleaning process of archaeological potsherds excavated from the excavation site at Abusir. Different analytical techniques, such as transmission electron microscope (TEM), digital microscope, stereomicroscope, scanning electron microscope (SEM-EDX), X-ray diffraction (XRD), and measurement of color change have been used to characterize the studied potsherds and evaluate the cleaning process. The results of the XRD analysis showed the presence of some main minerals, such as albite, quartz, diopside, hematite, spinel and chloride salt (halite). The results of the microscopic investigation used in the evaluation process revealed that using TiO2 NPs poultice perfectly removed soot and dust deposits from the surface, and the cleaned surface became smooth. The results of elemental analysis by (SEM-EDX) showed the effective reduction in the percentage of salts and soot from the treated potsherds by TiO2 NPs poultice to be 3.38% and 6.68%, respectively. The measurement of color change revealed that the treated potsherds by TiO2 NPs poultice gave the highest (ΔE*=9.41), confirming this poultice's effective role in cleaning archaeological potsherds. Based on the results of different analytical techniques used in the evaluation process, the TiO2 NPs poultice is recommended for use in the cleaning process of archaeological pottery.
{"title":"A Comparison Study of Titanium Dioxide and Zinc Oxide Nanoparticles for Cleaning Archaeological Pottery","authors":"H. Mohamed","doi":"10.4028/p-2zntbv","DOIUrl":"https://doi.org/10.4028/p-2zntbv","url":null,"abstract":"Many excavations contain potsherds that have suffered from different aspects of deterioration, including salt crystallization, dirt deposition, and soot. The different stains play an important role in the deterioration of archaeological pottery, such as the disappearance of the original surface and discoloration. The present study aims to evaluate some nanoparticles in an innovative poultice form to be used to clean archaeological pottery. In this study, the nanoparticles (NPs) of titanium dioxide (TiO2) and zinc oxide (ZnO) have been prepared at 5% and in the poultice form to be used for the cleaning process of archaeological potsherds excavated from the excavation site at Abusir. Different analytical techniques, such as transmission electron microscope (TEM), digital microscope, stereomicroscope, scanning electron microscope (SEM-EDX), X-ray diffraction (XRD), and measurement of color change have been used to characterize the studied potsherds and evaluate the cleaning process. The results of the XRD analysis showed the presence of some main minerals, such as albite, quartz, diopside, hematite, spinel and chloride salt (halite). The results of the microscopic investigation used in the evaluation process revealed that using TiO2 NPs poultice perfectly removed soot and dust deposits from the surface, and the cleaned surface became smooth. The results of elemental analysis by (SEM-EDX) showed the effective reduction in the percentage of salts and soot from the treated potsherds by TiO2 NPs poultice to be 3.38% and 6.68%, respectively. The measurement of color change revealed that the treated potsherds by TiO2 NPs poultice gave the highest (ΔE*=9.41), confirming this poultice's effective role in cleaning archaeological potsherds. Based on the results of different analytical techniques used in the evaluation process, the TiO2 NPs poultice is recommended for use in the cleaning process of archaeological pottery.","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"49 1","pages":"61 - 77"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78118033","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}
The introduction of antimicrobial nanoparticles into nanofiber coatings is significant for enhancing microbial corrosion protection. Here, electrospun polysulfone nanofiber (PSU-Nf) and PSU-Nf functionalized with biogenic silver nanoparticles (AgNPs) coatings (PSU-Nf-AgNPs) used for Cobalt (Co) corrosion resistance in a marine environment containing Aeromonas eucrenophila (A. eucrenophila). We utilized the barrier function of the PSU-Nf and the bacterial inhibition property of the AgNPs that are synthesized using bacteria. The thickness of nanofiber coatings was 233.11 ± 33.64 µm analyzed by optical microscope and beadless morphology of nanofibers was observed using scanning electron microscope (SEM). The corrosion behavior of Co coated with PSU-Nf and PSU-Nf-AgNPs in abiotic and in the presence of the bacterium environment was investigated via polarization techniques and electrochemical impedance spectroscopy (EIS). Corrosion analysis reveals that the charge transfer resistance (Rct) increased because of the addition of the nanostructure resulting in a reduction in corrosion rate. SEM micrographs show Co surface was severely damaged by a microbial corrosive attack with severe crevices. However, the PSU-Nf and especially PSU-Nf-AgNPs coated Co surface was still covered by nanofiber coatings as the bacteria colony was not noticed. In addition, the results of the performing bacterial disk diffusion method indicated that electrospun PSU-Nf-AgNPs have good antibacterial activity against Gram-positive, Gram-negative, and model biofilm bacterium. It was found that the uncoated Co surface had severe crevices and offered poor corrosion resistance under mineral salt medium with A. eucrenophila strain. Therefore, PSU-Nf-AgNPs coated Co exhibited better corrosion resistance in mineral salt medium containing bacteria.
{"title":"Antibacterial Polysulfone Nanofiber Functionalized with Green Silver Nanoparticles by a Facile Wetting Method for Microbial Corrosion Protection","authors":"Nalan Oya San Keskin, Furkan Deniz, H. Nazır","doi":"10.4028/p-4z44c3","DOIUrl":"https://doi.org/10.4028/p-4z44c3","url":null,"abstract":"The introduction of antimicrobial nanoparticles into nanofiber coatings is significant for enhancing microbial corrosion protection. Here, electrospun polysulfone nanofiber (PSU-Nf) and PSU-Nf functionalized with biogenic silver nanoparticles (AgNPs) coatings (PSU-Nf-AgNPs) used for Cobalt (Co) corrosion resistance in a marine environment containing Aeromonas eucrenophila (A. eucrenophila). We utilized the barrier function of the PSU-Nf and the bacterial inhibition property of the AgNPs that are synthesized using bacteria. The thickness of nanofiber coatings was 233.11 ± 33.64 µm analyzed by optical microscope and beadless morphology of nanofibers was observed using scanning electron microscope (SEM). The corrosion behavior of Co coated with PSU-Nf and PSU-Nf-AgNPs in abiotic and in the presence of the bacterium environment was investigated via polarization techniques and electrochemical impedance spectroscopy (EIS). Corrosion analysis reveals that the charge transfer resistance (Rct) increased because of the addition of the nanostructure resulting in a reduction in corrosion rate. SEM micrographs show Co surface was severely damaged by a microbial corrosive attack with severe crevices. However, the PSU-Nf and especially PSU-Nf-AgNPs coated Co surface was still covered by nanofiber coatings as the bacteria colony was not noticed. In addition, the results of the performing bacterial disk diffusion method indicated that electrospun PSU-Nf-AgNPs have good antibacterial activity against Gram-positive, Gram-negative, and model biofilm bacterium. It was found that the uncoated Co surface had severe crevices and offered poor corrosion resistance under mineral salt medium with A. eucrenophila strain. Therefore, PSU-Nf-AgNPs coated Co exhibited better corrosion resistance in mineral salt medium containing bacteria.","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"304 1","pages":"79 - 91"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86764181","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}
Hafida Ourihane, A. Guittoum, M. Hemmous, D. Martínez-Blanco, J. Blanco, P. Gorria, N. Boukherroub
Fe(Ni, Si) solid solutions were elaborated by high energy mechanical alloying from elemental Fe, Ni and Si powdersfor a milling time of 72 h. From X-ray diffraction (XRD) analysis, it has been shown that the Fe(Ni, Si) samples present a single phase in the whole range of Si content and exhibit a solid solution of disordered bcc α-Fe. The lattice parameter a (Å) of the new structures and the mean crystallitessize (nm) were found to decrease with increasing Si contents. In contrast, the microstrain behaviour presents two different stages as the Si contents are increased. Scanning Electron Microscopy (SEM) images confirmed the behaviour of the mean crystallites size, where it can be seen that the addition of Si promotes the reduction of the size of powder particles. The saturation magnetization Ms was found to decrease by a factor of almost 1.4 and the coercively was found to increase by a factor of almost 2.4, when the Si content was increased from x= 0 % to x= 20 %. The Mössbauer spectroscopy confirmed the local in site crystal locations of Si and Ni as they diffuse into the matrix of the bcc α-Fe structure to form a solid solution.
{"title":"Silicon-Doped Nanostructured Fe80Ni20 Alloys: The Role of Si on the Microstructure, Morphology and Magnetic Properties","authors":"Hafida Ourihane, A. Guittoum, M. Hemmous, D. Martínez-Blanco, J. Blanco, P. Gorria, N. Boukherroub","doi":"10.4028/p-6nyf2h","DOIUrl":"https://doi.org/10.4028/p-6nyf2h","url":null,"abstract":"Fe(Ni, Si) solid solutions were elaborated by high energy mechanical alloying from elemental Fe, Ni and Si powdersfor a milling time of 72 h. From X-ray diffraction (XRD) analysis, it has been shown that the Fe(Ni, Si) samples present a single phase in the whole range of Si content and exhibit a solid solution of disordered bcc α-Fe. The lattice parameter a (Å) of the new structures and the mean crystallitessize (nm) were found to decrease with increasing Si contents. In contrast, the microstrain behaviour presents two different stages as the Si contents are increased. Scanning Electron Microscopy (SEM) images confirmed the behaviour of the mean crystallites size, where it can be seen that the addition of Si promotes the reduction of the size of powder particles. The saturation magnetization Ms was found to decrease by a factor of almost 1.4 and the coercively was found to increase by a factor of almost 2.4, when the Si content was increased from x= 0 % to x= 20 %. The Mössbauer spectroscopy confirmed the local in site crystal locations of Si and Ni as they diffuse into the matrix of the bcc α-Fe structure to form a solid solution.","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"2 1","pages":"1 - 14"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90119869","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}
In this study, the effect of Mn doping concentration on the structural, microstructural, linear and nonlinear optical properties of ZnO was investigated. Pristine and Mn-doped ZnO films were prepared by chemical bath deposition on a glass substrate. The crystal structure and surface morphology of the films were determined by X-ray diffraction and force electron scanning microscopy (FESEM). X-Ray Diffraction (XRD) analysis revealed that the films had a polycrystalline structure and all films were ZnO with a hexagonal structure. In addition, a shift was detected in the XRD pattern of the films with the Mn doping process. According to the FESEM results, the surface of the films has irregularly shaped particles. Linear and nonlinear optical parameters were estimated using transmittance and absorbance measurements. And then, optical absorption coefficient, extinction coefficient, refractive index, optical dielectric constants, surface, and volume energy loss functions, optical band gap values, and optical and electrical conductivity were determined as linear optical properties. It was determined that these properties were affected by Mn-doped ratios. It was determined that nonlinear optical properties such as linear optical properties were also affected by the doping process.
{"title":"Chemical Bath Deposition Grown Zno Thin Films: Role of Manganese Doping","authors":"E. Güneri, H. Johnson, F. Göde","doi":"10.4028/p-0feb08","DOIUrl":"https://doi.org/10.4028/p-0feb08","url":null,"abstract":"In this study, the effect of Mn doping concentration on the structural, microstructural, linear and nonlinear optical properties of ZnO was investigated. Pristine and Mn-doped ZnO films were prepared by chemical bath deposition on a glass substrate. The crystal structure and surface morphology of the films were determined by X-ray diffraction and force electron scanning microscopy (FESEM). X-Ray Diffraction (XRD) analysis revealed that the films had a polycrystalline structure and all films were ZnO with a hexagonal structure. In addition, a shift was detected in the XRD pattern of the films with the Mn doping process. According to the FESEM results, the surface of the films has irregularly shaped particles. Linear and nonlinear optical parameters were estimated using transmittance and absorbance measurements. And then, optical absorption coefficient, extinction coefficient, refractive index, optical dielectric constants, surface, and volume energy loss functions, optical band gap values, and optical and electrical conductivity were determined as linear optical properties. It was determined that these properties were affected by Mn-doped ratios. It was determined that nonlinear optical properties such as linear optical properties were also affected by the doping process.","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"127 1","pages":"107 - 130"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80090140","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}
I. Haq, A. W. Anwar, Zunair Arslan, Abdul Waheed, U. Ilyas, F. Nasreen
Lithium sulfur (Li-S) batteries have become one of the promising rechargeable storage devices due to its abundancy, low cost, non-toxicity, environmental friendliness and high theoretical specific capacity. However, the insulating nature of sulfur and the shuttling effect of polysulfides have limited their applications. In order to alleviate these problems and make Li-S batteries more promising, we have synthesized a composite of reduced graphene oxide and sulfur (rGO-S) as electrode material for these batteries. In this paper, graphite oxide was prepared from graphite powder by Improved Hummer’s method followed by ultrasonic exfoliation to make Graphene Oxide (GO). The GO suspension was hydrothermally reduced and heated in a hot air oven at 150 °C for 4 hours followed by the addition of sulfur (S) in a ratio of 0.1:1 and 1:1 by mass and heated again at 180 °C for another 4 hours to make a composite of rGO-S. The electrode of the rGO-S composite was prepared by making a slurry of active material, carbon black and polyvinylidene fluoride (PVDF). The sample of GO and rGO were analyzed using Ultraviolet (UV)-Visible and Fourier Transform Infrared (FTIR) spectroscopy. The composite material was analyzed using X-Rays Powder Diffraction (XRD) while the energy density and charge discharge curves of the electrode were analyzed using cyclic voltammetry (CV).
{"title":"Synthesis and Investigation of Reduced Graphene Oxide - Sulfur Composite Electrode for Lithium-Sulfur Battery","authors":"I. Haq, A. W. Anwar, Zunair Arslan, Abdul Waheed, U. Ilyas, F. Nasreen","doi":"10.4028/p-f944iu","DOIUrl":"https://doi.org/10.4028/p-f944iu","url":null,"abstract":"Lithium sulfur (Li-S) batteries have become one of the promising rechargeable storage devices due to its abundancy, low cost, non-toxicity, environmental friendliness and high theoretical specific capacity. However, the insulating nature of sulfur and the shuttling effect of polysulfides have limited their applications. In order to alleviate these problems and make Li-S batteries more promising, we have synthesized a composite of reduced graphene oxide and sulfur (rGO-S) as electrode material for these batteries. In this paper, graphite oxide was prepared from graphite powder by Improved Hummer’s method followed by ultrasonic exfoliation to make Graphene Oxide (GO). The GO suspension was hydrothermally reduced and heated in a hot air oven at 150 °C for 4 hours followed by the addition of sulfur (S) in a ratio of 0.1:1 and 1:1 by mass and heated again at 180 °C for another 4 hours to make a composite of rGO-S. The electrode of the rGO-S composite was prepared by making a slurry of active material, carbon black and polyvinylidene fluoride (PVDF). The sample of GO and rGO were analyzed using Ultraviolet (UV)-Visible and Fourier Transform Infrared (FTIR) spectroscopy. The composite material was analyzed using X-Rays Powder Diffraction (XRD) while the energy density and charge discharge curves of the electrode were analyzed using cyclic voltammetry (CV).","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"222 1","pages":"15 - 27"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79959984","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}
Monoclinic Ag2S nanoparticles have been synthesized via a thermal decomposition of Ag(I) complex of N-methyl-N-phenyl dithiocarbamate (as a single source precursor) in oleylamine at 180 °C. The complex was characterized by spectroscopic techniques. The decomposition profile was studied using thermogravimetry analysis (TGA) coupled to differential scanning calorimetry (DSC), and the results obtained from these characterization techniques confirmed the formation of the silver dithiocarbamate complex. The Ag2S nanoparticles was characterized using X-ray diffraction, energy dispersive X-ray spectrometer (EDS), transmission electron microscopy (TEM), UV-visible spectroscopy, and fourier transform infra-red (FTIR) spectroscopy. The XRD patterns of the silver sulphide nanoparticles confirmed acanthite phase, with the most prominent (-121) peak identified at 2θ value of 34.39o, while EDS analysis showed Ag:S ratio of 2:1, which agreed with the XRD result. FTIR spectrum revealed the presence of amine groups, thereby confirmed that the synthesized Ag2S was capped by oleylamine. Finally, the antioxidant activity of the Ag2S was determined by using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay and it exhibited better antioxidant activities than silver nanoparticles.
采用n -甲基- n -苯基二硫代氨基甲酸酯(n -甲基- n -苯基二硫代氨基甲酸酯)的Ag(I)配合物(作为单源前驱体)在油胺中180℃热分解法制备了单斜晶Ag2S纳米颗粒。用光谱技术对该配合物进行了表征。利用热重分析(TGA)和差示扫描量热分析(DSC)对分解剖面进行了研究，这些表征技术的结果证实了二硫代氨基甲酸银络合物的形成。采用x射线衍射、能谱仪(EDS)、透射电子显微镜(TEM)、紫外可见光谱和傅里叶变换红外光谱(FTIR)对Ag2S纳米颗粒进行了表征。硫化银纳米颗粒的XRD谱图证实为棘长石相，在2θ值为34.39o处发现了最突出的(-121)峰，EDS分析显示Ag:S比为2:1，与XRD结果一致。FTIR光谱显示了胺基的存在，从而证实了合成的Ag2S被油胺覆盖。最后，采用DPPH法测定Ag2S的抗氧化活性，结果表明Ag2S的抗氧化活性优于纳米银。
{"title":"Synthesis and Antioxidant Investigation of Ag2S Nanoparticles Obtained from Silver(I) Complex of N-Methyl-N-Phenyl- Dithiocarbamate","authors":"T. Ajiboye, D. Onwudiwe","doi":"10.4028/p-f5c470","DOIUrl":"https://doi.org/10.4028/p-f5c470","url":null,"abstract":"Monoclinic Ag2S nanoparticles have been synthesized via a thermal decomposition of Ag(I) complex of N-methyl-N-phenyl dithiocarbamate (as a single source precursor) in oleylamine at 180 °C. The complex was characterized by spectroscopic techniques. The decomposition profile was studied using thermogravimetry analysis (TGA) coupled to differential scanning calorimetry (DSC), and the results obtained from these characterization techniques confirmed the formation of the silver dithiocarbamate complex. The Ag2S nanoparticles was characterized using X-ray diffraction, energy dispersive X-ray spectrometer (EDS), transmission electron microscopy (TEM), UV-visible spectroscopy, and fourier transform infra-red (FTIR) spectroscopy. The XRD patterns of the silver sulphide nanoparticles confirmed acanthite phase, with the most prominent (-121) peak identified at 2θ value of 34.39o, while EDS analysis showed Ag:S ratio of 2:1, which agreed with the XRD result. FTIR spectrum revealed the presence of amine groups, thereby confirmed that the synthesized Ag2S was capped by oleylamine. Finally, the antioxidant activity of the Ag2S was determined by using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay and it exhibited better antioxidant activities than silver nanoparticles.","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"47 1","pages":"131 - 143"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76046778","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}
S. Sharif, Z. Ahmad, Clare Hoskins, M. A. Choudhary, A. Mehmood
: The mixing of ethylene glycol (EG) with diethylene glycol (DEG) has been studied to analyse the effect of viscosity rise of solvent on the Ag nanostructures and their morphologies. The rise of viscosity has been adjusted by increasing the molar ratio of DEG to EG under optimized conditions of temperature and capping agent- polyvinylpyrrolidone (PVP). It has been seen that increasing the proportion of DEG resulted increasing the viscosity of solution and thus decreased the diameter of nanowires. The production of quantum nanowires has further become possible during reaction. The synthesized material was characterized using UV−Vis spectroscopy, SEM, EDX, XRD, PL and DSC. Surface Plasmon resonance and luminescence was determined using UV−Vis spectroscopy and PL spectroscopy. The data showed that Ag nanowires have a strong absorption band at 356 nm and 401 nm which can be attributed to the transverse and longitudinal surface Plasmon resonance. The XRD results indicated that the prepared product is made of pure Ag with face centred cubic structure, and the DSC analysis demonstrated the presence of amorphous domain within metal nanostructures. Finally, temperature fluctuations have caused the formation of nanoparticle of different shapes and sizes which bears the synthetic mechanistic insights. Our research work supplies new evidence to illustrate the actual growth mechanism and kinetics of silver nanowires. The main objective of this study is to investigate the effect of solvent in polyol synthesis of silver nanowires (Ag NWs) on the nanostructures diameter and morphologies
{"title":"Ag Nanostructure Morphologies and Physicochemical Properties Dictated by the Polyols Used in the Synthesis","authors":"S. Sharif, Z. Ahmad, Clare Hoskins, M. A. Choudhary, A. Mehmood","doi":"10.4028/p-c41elh","DOIUrl":"https://doi.org/10.4028/p-c41elh","url":null,"abstract":": The mixing of ethylene glycol (EG) with diethylene glycol (DEG) has been studied to analyse the effect of viscosity rise of solvent on the Ag nanostructures and their morphologies. The rise of viscosity has been adjusted by increasing the molar ratio of DEG to EG under optimized conditions of temperature and capping agent- polyvinylpyrrolidone (PVP). It has been seen that increasing the proportion of DEG resulted increasing the viscosity of solution and thus decreased the diameter of nanowires. The production of quantum nanowires has further become possible during reaction. The synthesized material was characterized using UV−Vis spectroscopy, SEM, EDX, XRD, PL and DSC. Surface Plasmon resonance and luminescence was determined using UV−Vis spectroscopy and PL spectroscopy. The data showed that Ag nanowires have a strong absorption band at 356 nm and 401 nm which can be attributed to the transverse and longitudinal surface Plasmon resonance. The XRD results indicated that the prepared product is made of pure Ag with face centred cubic structure, and the DSC analysis demonstrated the presence of amorphous domain within metal nanostructures. Finally, temperature fluctuations have caused the formation of nanoparticle of different shapes and sizes which bears the synthetic mechanistic insights. Our research work supplies new evidence to illustrate the actual growth mechanism and kinetics of silver nanowires. The main objective of this study is to investigate the effect of solvent in polyol synthesis of silver nanowires (Ag NWs) on the nanostructures diameter and morphologies","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"15 1","pages":"93 - 106"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84386791","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}
Arsen E. Hafarov, D. I. Trubchaninova, A. Burmak, M. Karpets, I. Vladymyrskyi, A. Kaidatzis, Dimitros Niarchos
We study the crystal structure of carbon-doped Al-rich MnAl thin films deposited on Si substrates. The effects of carbon content and vacuum heat treatment parameters are studied. It is shown that the carbon content, in combination to heat treatment, allows to tailor structural phase transitions in the films. The main phases detected are Al2Mn3, pure Mn, and pure C. As carbon content increases, the amount of Al2Mn3 phase decreases and the content of pure crystallized Mn phase increases. In addition, it is shown that as the heat treatment temperature increases – up to 500 °C – the Al2Mn3 phase content increases, whereas a pure C phase appears at lower temperatures.
{"title":"Structural Phase Transitions in Al-Rich C-Doped Mnal Thin Films","authors":"Arsen E. Hafarov, D. I. Trubchaninova, A. Burmak, M. Karpets, I. Vladymyrskyi, A. Kaidatzis, Dimitros Niarchos","doi":"10.4028/p-801jk8","DOIUrl":"https://doi.org/10.4028/p-801jk8","url":null,"abstract":"We study the crystal structure of carbon-doped Al-rich MnAl thin films deposited on Si substrates. The effects of carbon content and vacuum heat treatment parameters are studied. It is shown that the carbon content, in combination to heat treatment, allows to tailor structural phase transitions in the films. The main phases detected are Al2Mn3, pure Mn, and pure C. As carbon content increases, the amount of Al2Mn3 phase decreases and the content of pure crystallized Mn phase increases. In addition, it is shown that as the heat treatment temperature increases – up to 500 °C – the Al2Mn3 phase content increases, whereas a pure C phase appears at lower temperatures.","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"46 1","pages":"29 - 37"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90907834","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}
Haiyan Guan, Yajun Lei, Qing Chen, Jiao Ding, Hongwei Lei, Yaxiong Guo, Zuo Jun Tan, F. Xiang
The production of nitrogen-doped carbon quantum dots (N-CDs) from walnut shell waste is crucially important for green chemistry and sustainable development. Herein we fabricate N-CDs by a bottom-up solvothermal method and use the novel N-CDs to modify the electron transport layer (ETL) in perovskite solar cells (PVSCs). The N-CDs can produce 440 nm fluorescence under the excitation of 350 nm light with a quantum yield of 8.75%. Infrared absorption spectra show that N-CDs contain high proportions of nitrogen-containing and oxygen-containing functional groups. , Through the incorporation of N-CDs into SnO2 ETL, the formation of defects is inhibited, and crystallinity is improved. This is because the N-CDs contains a large number of functional groups such as nitrogen and oxygen and these groups would interact with the ETL and perovskite, which reduce the defect/trap centers in PVSCs. Therefore, the N-CDs modified PVSCs show improved power conversion efficiency. This study provides a novel way to use walnut shell waste to synthesize N-CDs and achieve efficient and stable perovskites solar cells.
{"title":"Synthesis of Nitrogen-Doped Carbon Quantum Dots from Walnut Shell Waste as Electron Transport Layer Additive for Perovskite Solar Cells","authors":"Haiyan Guan, Yajun Lei, Qing Chen, Jiao Ding, Hongwei Lei, Yaxiong Guo, Zuo Jun Tan, F. Xiang","doi":"10.4028/p-3tw4x3","DOIUrl":"https://doi.org/10.4028/p-3tw4x3","url":null,"abstract":"The production of nitrogen-doped carbon quantum dots (N-CDs) from walnut shell waste is crucially important for green chemistry and sustainable development. Herein we fabricate N-CDs by a bottom-up solvothermal method and use the novel N-CDs to modify the electron transport layer (ETL) in perovskite solar cells (PVSCs). The N-CDs can produce 440 nm fluorescence under the excitation of 350 nm light with a quantum yield of 8.75%. Infrared absorption spectra show that N-CDs contain high proportions of nitrogen-containing and oxygen-containing functional groups. , Through the incorporation of N-CDs into SnO2 ETL, the formation of defects is inhibited, and crystallinity is improved. This is because the N-CDs contains a large number of functional groups such as nitrogen and oxygen and these groups would interact with the ETL and perovskite, which reduce the defect/trap centers in PVSCs. Therefore, the N-CDs modified PVSCs show improved power conversion efficiency. This study provides a novel way to use walnut shell waste to synthesize N-CDs and achieve efficient and stable perovskites solar cells.","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"49 2 1","pages":"49 - 60"},"PeriodicalIF":1.7,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78404737","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}
Rusya Iryanti Yahaya, N. Arifin, F. Ali, Siti Sarwani Putri Mohamed Isa
The impact of nanoparticle shapes (i.e., blade, brick, cylindrical, platelet, and spherical) on the MHD flow of Ag-MgO/water hybrid nanofluid over a stretching/shrinking sheet is scrutinized in this study. Chemical reaction and activation energy are included in the governing partial differential equations of the flow problem. On the boundary, velocity slip and zero mass flux conditions are considered. The simplification of the governing equations and boundary conditions into non-linear ordinary differential equations is done through similarity transformation. Then, the bvp4c solver in Matlab is deployed for computation, with the results generated in the form of numerical solutions and graphs. It is found that the usage of spherical-shaped nanoparticles produces the lowest magnitude of skin friction coefficient, and the implementation of blade-shaped nanoparticles in the hybrid nanofluid provides the highest enhancement of heat transfer rate. The increment in activation energy slows down the chemical reaction that raises the concentration profile of the hybrid nanofluid. However, the concentration profile decreases as the reaction rate increases.
{"title":"Nanoparticle Shapes Effects on MHD Flow of Hybrid Nanofluid over a Stretching/Shrinking Sheet with Slip and Chemical Reaction","authors":"Rusya Iryanti Yahaya, N. Arifin, F. Ali, Siti Sarwani Putri Mohamed Isa","doi":"10.4028/p-wwb62a","DOIUrl":"https://doi.org/10.4028/p-wwb62a","url":null,"abstract":"The impact of nanoparticle shapes (i.e., blade, brick, cylindrical, platelet, and spherical) on the MHD flow of Ag-MgO/water hybrid nanofluid over a stretching/shrinking sheet is scrutinized in this study. Chemical reaction and activation energy are included in the governing partial differential equations of the flow problem. On the boundary, velocity slip and zero mass flux conditions are considered. The simplification of the governing equations and boundary conditions into non-linear ordinary differential equations is done through similarity transformation. Then, the bvp4c solver in Matlab is deployed for computation, with the results generated in the form of numerical solutions and graphs. It is found that the usage of spherical-shaped nanoparticles produces the lowest magnitude of skin friction coefficient, and the implementation of blade-shaped nanoparticles in the hybrid nanofluid provides the highest enhancement of heat transfer rate. The increment in activation energy slows down the chemical reaction that raises the concentration profile of the hybrid nanofluid. However, the concentration profile decreases as the reaction rate increases.","PeriodicalId":16525,"journal":{"name":"Journal of Nano Research","volume":"80 1","pages":"139 - 158"},"PeriodicalIF":1.7,"publicationDate":"2022-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86836827","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}
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