Pub Date : 2024-07-18DOI: 10.25159/3005-2602/15935
S. Ezike, Mustafa S. Adamu, Emmanuel Ike, M. A. Salawu, Pascal Timtere, R. Obodo
The emergence of the multidisciplinary field of nanoscience with potential applications in medicine, cosmetics, renewable energy, agriculture and environmental remediation has led scientists to search for safer methods of synthesising nanoparticles. We based this study on the synthesis of silver nanoparticles (AgNPs) for varying immersion times of 30, 60, 90, 120 and 150 min, while employing Adansonia digitata as a reducing and capping agent and labelled A, B, C, D and E, respectively. The X-ray diffraction (XRD) pattern of the synthesised AgNPs for all samples have three peaks positioned at 2θ = 37.94°, 44.07° and 64.37° corresponding to (111), (200) and (220) planes, respectively. The samples have a preferred orientation at 2θ = 37.94° corresponding to (111) plane irrespective of the duration of immersion of Adansonia digitata root extracts. The preferred intense peak shows a polycrystalline phase composition of the green synthesised AgNPs, demonstrating the creation of face-centred cubic crystalline of AgNPs. The intrinsic stress, σs, dislocation density, δ, specific surface area, S, crystallite size (D), surface area (S) to volume (V) ratio, lattice parameter, a and atomic packing factor were calculated from XRD data and presented. The particle sizes obtained from the SEM analysis are 69.88, 18.69, 15.45, 19.64 and 20.08 nm for samples A, B, C, D and E, respectively. The optical energy band gaps are 2.37 eV, 2.42 eV, 2.59 eV, 2.52 eV and 2.34 eV for samples A, B, C, D and E respectively. The synthesised AgNPs can be used in energy storage and conversions owing to their properties.
{"title":"Influence of Adansonia digitata Stem Extract Immersion Time on Properties of Biosynthesised Silver Nanoparticles","authors":"S. Ezike, Mustafa S. Adamu, Emmanuel Ike, M. A. Salawu, Pascal Timtere, R. Obodo","doi":"10.25159/3005-2602/15935","DOIUrl":"https://doi.org/10.25159/3005-2602/15935","url":null,"abstract":"The emergence of the multidisciplinary field of nanoscience with potential applications in medicine, cosmetics, renewable energy, agriculture and environmental remediation has led scientists to search for safer methods of synthesising nanoparticles. We based this study on the synthesis of silver nanoparticles (AgNPs) for varying immersion times of 30, 60, 90, 120 and 150 min, while employing Adansonia digitata as a reducing and capping agent and labelled A, B, C, D and E, respectively. The X-ray diffraction (XRD) pattern of the synthesised AgNPs for all samples have three peaks positioned at 2θ = 37.94°, 44.07° and 64.37° corresponding to (111), (200) and (220) planes, respectively. The samples have a preferred orientation at 2θ = 37.94° corresponding to (111) plane irrespective of the duration of immersion of Adansonia digitata root extracts. The preferred intense peak shows a polycrystalline phase composition of the green synthesised AgNPs, demonstrating the creation of face-centred cubic crystalline of AgNPs. The intrinsic stress, σs, dislocation density, δ, specific surface area, S, crystallite size (D), surface area (S) to volume (V) ratio, lattice parameter, a and atomic packing factor were calculated from XRD data and presented. The particle sizes obtained from the SEM analysis are 69.88, 18.69, 15.45, 19.64 and 20.08 nm for samples A, B, C, D and E, respectively. The optical energy band gaps are 2.37 eV, 2.42 eV, 2.59 eV, 2.52 eV and 2.34 eV for samples A, B, C, D and E respectively. The synthesised AgNPs can be used in energy storage and conversions owing to their properties.","PeriodicalId":210951,"journal":{"name":"Nano-Horizons: Journal of Nanosciences and Nanotechnologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141824294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-04DOI: 10.25159/3005-2602/14260
Esmaeil Salahi, Hoda Enayati Taloobaghi, Mohammad Mahdi Shahidi, Fabien Ezema
In this study, we prepared a ZnO thin film using the sol-gel spin-coating method on glass substrates. We repeated the synthesis procedure once, twice and four times to obtain the samples. We then investigated the FESEM images, XRD diffractograms, Hall effect and dielectric measurement of the samples. We observed the phase transition from the wurtzite to the zinc blende phase as a result of the number of repetitions. The films exhibited direct band gaps ranging from 3.2 eV to 3.3 eV. This result indicate that the two-times synthesis process has considerably affected the morphology and also improved the crystallinity of the layer. The sample of which the surface was covered with nearly uniform short nanorod grains with an average diameter of ~ 180 nm showed the highest sensitivity to ultraviolet light.
在这项研究中，我们采用溶胶-凝胶旋涂法在玻璃基底上制备了氧化锌薄膜。我们分别重复了一次、两次和四次合成过程，最终获得了样品。然后，我们研究了样品的 FESEM 图像、XRD 衍射图、霍尔效应和介电测量。我们观察到，随着重复次数的增加，相变从乌兹石相转变为锌混晶相。薄膜的直接带隙在 3.2 eV 至 3.3 eV 之间。这一结果表明，两次合成过程极大地影响了膜层的形态，同时也提高了膜层的结晶度。表面覆盖着近乎均匀的短纳米棒晶粒（平均直径约为 180 nm）的样品对紫外线的灵敏度最高。
{"title":"Investigating the Dielectric Photosensitivity of Zinc Oxide Nanostructures Under Ultraviolet Light","authors":"Esmaeil Salahi, Hoda Enayati Taloobaghi, Mohammad Mahdi Shahidi, Fabien Ezema","doi":"10.25159/3005-2602/14260","DOIUrl":"https://doi.org/10.25159/3005-2602/14260","url":null,"abstract":"In this study, we prepared a ZnO thin film using the sol-gel spin-coating method on glass substrates. We repeated the synthesis procedure once, twice and four times to obtain the samples. We then investigated the FESEM images, XRD diffractograms, Hall effect and dielectric measurement of the samples. We observed the phase transition from the wurtzite to the zinc blende phase as a result of the number of repetitions. The films exhibited direct band gaps ranging from 3.2 eV to 3.3 eV. This result indicate that the two-times synthesis process has considerably affected the morphology and also improved the crystallinity of the layer. The sample of which the surface was covered with nearly uniform short nanorod grains with an average diameter of ~ 180 nm showed the highest sensitivity to ultraviolet light.","PeriodicalId":210951,"journal":{"name":"Nano-Horizons: Journal of Nanosciences and Nanotechnologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140744338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-20DOI: 10.25159/3005-2602/14875
M. Ndiaye, O. Sakh, A. Seck, B. Ngom, M. Maaza, M. Chaker
In this study, we report on the valence control of vanadium oxidation states towards stabilising VO2 thin films. X-ray diffraction measurements indicate that up to 300 kGy of gamma-ray radiation the VO2 phase remains monoclinic, with the crystallite size only varying slightly with the dose. X-ray photoemission spectroscopy indicates the presence of three oxide phases (VO2, V2O3 and V2O5) on the samples. A decrease in the oxidation states of V3+ and V5+ and an increase in the valence state V4+ are observed for irradiations up to 300 kGy, which favours the vanadium dioxide VO2 formation.
{"title":"Selective Gamma-Ray Ionisation of Vanadium Oxides: Towards the Formation of VO2","authors":"M. Ndiaye, O. Sakh, A. Seck, B. Ngom, M. Maaza, M. Chaker","doi":"10.25159/3005-2602/14875","DOIUrl":"https://doi.org/10.25159/3005-2602/14875","url":null,"abstract":"In this study, we report on the valence control of vanadium oxidation states towards stabilising VO2 thin films. X-ray diffraction measurements indicate that up to 300 kGy of gamma-ray radiation the VO2 phase remains monoclinic, with the crystallite size only varying slightly with the dose. X-ray photoemission spectroscopy indicates the presence of three oxide phases (VO2, V2O3 and V2O5) on the samples. A decrease in the oxidation states of V3+ and V5+ and an increase in the valence state V4+ are observed for irradiations up to 300 kGy, which favours the vanadium dioxide VO2 formation.","PeriodicalId":210951,"journal":{"name":"Nano-Horizons: Journal of Nanosciences and Nanotechnologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138958513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-12-05DOI: 10.25159/3005-2602/13789
I. Ngom, A. Fall, Samba Sarr, Baye Modou Ndiaye, Seynabou Mbodj, Remy Bucher, B. Ngom
In this study, we investigated the effects of the annealing temperatures on the physical properties of zinc oxide nanoparticles produced by the decomposition of the hydrozincite obtained from Adansonia digitata leaves. The results of the X-ray diffraction revealed the formation of well-crystallised hexagonal zinc oxide with an average crystallite size of 11.80 nm, 11.90 nm, 11.97 nm and 15.28 nm for the samples annealed at 400 °C, 500 °C, 600 °C and 700 °C, respectively. The crystallite size of the hydrozincite constituting the unannealed sample was 22 nm. In the spectra of the Fourier transform infrared spectroscopy, the appearance of the peaks at 520 cm-1 for all synthesised materials confirms the formation of pure wurtzite zinc oxide. The band gap determined from diffuse reflectance ultraviolet-visible spectroscopy was found to be 3.19 eV, 3.21 eV, 3.23 eV and 3.24 eV for the samples annealed at 400 °C, 500 °C, 600 °C and 700 °C, respectively. These values increase with the annealing temperature and are still lower than the band gap of pure bulk zinc oxide (3.3 eV) owing to the structural defects as confirmed by the broad emission bands in the visible depicted from the photoluminescence analysis.
{"title":"Physical Properties of ZnO-NPs Induced by the Thermal Annealing of Hydrozincite Derived from Adansonia Digitata Leaves Extract","authors":"I. Ngom, A. Fall, Samba Sarr, Baye Modou Ndiaye, Seynabou Mbodj, Remy Bucher, B. Ngom","doi":"10.25159/3005-2602/13789","DOIUrl":"https://doi.org/10.25159/3005-2602/13789","url":null,"abstract":"In this study, we investigated the effects of the annealing temperatures on the physical properties of zinc oxide nanoparticles produced by the decomposition of the hydrozincite obtained from Adansonia digitata leaves. The results of the X-ray diffraction revealed the formation of well-crystallised hexagonal zinc oxide with an average crystallite size of 11.80 nm, 11.90 nm, 11.97 nm and 15.28 nm for the samples annealed at 400 °C, 500 °C, 600 °C and 700 °C, respectively. The crystallite size of the hydrozincite constituting the unannealed sample was 22 nm. In the spectra of the Fourier transform infrared spectroscopy, the appearance of the peaks at 520 cm-1 for all synthesised materials confirms the formation of pure wurtzite zinc oxide. The band gap determined from diffuse reflectance ultraviolet-visible spectroscopy was found to be 3.19 eV, 3.21 eV, 3.23 eV and 3.24 eV for the samples annealed at 400 °C, 500 °C, 600 °C and 700 °C, respectively. These values increase with the annealing temperature and are still lower than the band gap of pure bulk zinc oxide (3.3 eV) owing to the structural defects as confirmed by the broad emission bands in the visible depicted from the photoluminescence analysis.","PeriodicalId":210951,"journal":{"name":"Nano-Horizons: Journal of Nanosciences and Nanotechnologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138598809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-17DOI: 10.25159/3005-2602/13835
Ayesha Kausar, Ishaq Ahmad
In this article, we overview a very important type of natural fibre, namely, hemp fibre. We consider the exclusive structure, properties, modification, the composite or nanocomposite formation and exceptional application zones. Industrial hemp fibres have been commonly developed and possess high cellulose amounts. The long hemp fibres can be termed bast or flax fibres. Hemp fibres are eco-friendly, and have light weightiness and stiffness properties. Consequently, to enhance the use of hemp fibres at engineering level, research has focused on improving the mechanical or thermal and high-tech features of these fibres. In doing this, the surface modification or treatment of hemp fibres has been notably considered. The modified fibres have been found valuable for developing certain derived materials such as polymeric composites and nanocomposites in particular. Consequently, including hemp fibres as additives in composite or nanocomposite matrices has been explored for manufacturing high performance ecological, recyclable, biodegradable and sustainable materials. Application areas identified for the hemp and related composites or nanocomposites include the synchrotron and neutron scattering, water treatment aiming dye removal, automobiles, textiles and construction. However, there is insufficient literature on these technologically important fibres and ensuing materials. Comprehensive future efforts may better resolve the challenges regarding reproducibility and long life-cycle high-tech applications of hemp fibres.
{"title":"Hemp Fibres: Essentials, Composites or Nanocomposites and Technical Applications","authors":"Ayesha Kausar, Ishaq Ahmad","doi":"10.25159/3005-2602/13835","DOIUrl":"https://doi.org/10.25159/3005-2602/13835","url":null,"abstract":"In this article, we overview a very important type of natural fibre, namely, hemp fibre. We consider the exclusive structure, properties, modification, the composite or nanocomposite formation and exceptional application zones. Industrial hemp fibres have been commonly developed and possess high cellulose amounts. The long hemp fibres can be termed bast or flax fibres. Hemp fibres are eco-friendly, and have light weightiness and stiffness properties. Consequently, to enhance the use of hemp fibres at engineering level, research has focused on improving the mechanical or thermal and high-tech features of these fibres. In doing this, the surface modification or treatment of hemp fibres has been notably considered. The modified fibres have been found valuable for developing certain derived materials such as polymeric composites and nanocomposites in particular. Consequently, including hemp fibres as additives in composite or nanocomposite matrices has been explored for manufacturing high performance ecological, recyclable, biodegradable and sustainable materials. Application areas identified for the hemp and related composites or nanocomposites include the synchrotron and neutron scattering, water treatment aiming dye removal, automobiles, textiles and construction. However, there is insufficient literature on these technologically important fibres and ensuing materials. Comprehensive future efforts may better resolve the challenges regarding reproducibility and long life-cycle high-tech applications of hemp fibres.","PeriodicalId":210951,"journal":{"name":"Nano-Horizons: Journal of Nanosciences and Nanotechnologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139265072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-04DOI: 10.25159/3005-2602/13831
A. Nkele, David C. Okeudo, B. Obitte, F. Ezema
In this article, we focused on studying the characteristics of sodium dodecyl sulfate-assisted zinc oxide materials synthesised using molybdenum as a dopant at varying concentrations of 0 M, 0.3 M and 0.5 M. The structural, morphological, elemental and optical characterisations of the synthesised films were studied using scanning electron microscopy, X-ray diffractometry, energy dispersive X-ray spectroscopy, and an ultraviolet-visible spectrophotometer. Nanorod morphology yielded a hexagonal wurtzite structure from the morphological and structural results. Plots from energy dispersive X-rays confirmed the presence of basic elemental constituents: zinc, oxygen and molybdenum. The optical results gave high absorbance and reduced reflectance trends for the doped samples towards lower wavelength regions. The undoped, 0.3 M and 0.5 M molybdenum-doped zinc oxide films recorded energy band gap values of 3.70 eV, 3.84 eV and 3.97 eV respectively. The prepared zinc oxide films would be useful in solar cell and optoelectronic devices.
{"title":"A Study on the Properties of Sodium Dodecyl Sulfate Surfactant-Assisted Zinc Oxide Thin Films Doped with Molybdenum","authors":"A. Nkele, David C. Okeudo, B. Obitte, F. Ezema","doi":"10.25159/3005-2602/13831","DOIUrl":"https://doi.org/10.25159/3005-2602/13831","url":null,"abstract":"In this article, we focused on studying the characteristics of sodium dodecyl sulfate-assisted zinc oxide materials synthesised using molybdenum as a dopant at varying concentrations of 0 M, 0.3 M and 0.5 M. The structural, morphological, elemental and optical characterisations of the synthesised films were studied using scanning electron microscopy, X-ray diffractometry, energy dispersive X-ray spectroscopy, and an ultraviolet-visible spectrophotometer. Nanorod morphology yielded a hexagonal wurtzite structure from the morphological and structural results. Plots from energy dispersive X-rays confirmed the presence of basic elemental constituents: zinc, oxygen and molybdenum. The optical results gave high absorbance and reduced reflectance trends for the doped samples towards lower wavelength regions. The undoped, 0.3 M and 0.5 M molybdenum-doped zinc oxide films recorded energy band gap values of 3.70 eV, 3.84 eV and 3.97 eV respectively. The prepared zinc oxide films would be useful in solar cell and optoelectronic devices.","PeriodicalId":210951,"journal":{"name":"Nano-Horizons: Journal of Nanosciences and Nanotechnologies","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128300101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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