Pub Date : 2023-07-12DOI: 10.1088/2043-6262/ace184
D. Neupane, Jacob Casey, Jolaikha Sultana, A. Pathak, S. Karna, S. Pollard, S. Mishra
Single-phase Gd2O3 nanostructures with different morphologies, such as nanoparticles, nanorods, nanospheres, and nanoplates, were synthesised. Gd2O3 1D nanorods and 2D nanoplate architectures were prepared via the hydrothermal method, while 3D hollow nanospheres were synthesised via homogeneous precipitation. The magnetic and magnetocaloric properties of Gd2O3 nanostructured particles were studied as functions of temperature and field. The material demonstrated typical paramagnetic behaviour in the measured temperature range of 3–300 K. The magnetic entropy change (−ΔS M ) was determined from the magnetic isotherms measured in the 3–38 K temperature range in the field up to 5 T. The maximum change in magnetic entropy ΔSMmax value 11.2 J kg−1 K−1 for the nanoplate, 9.4 J kg−1 K−1 for the nanorod, 9.2 J kg−1 K−1 for the nanosphere, and 10.7 J kg−1 K−1 for the nanoparticle sample was observed at temperature 5 K for the magnetic field of 5 T. Owing to large ΔSMmax, these Gd2O3 nanostructured particles would be considered promising materials for magnetic refrigeration at cryogenic temperatures.
合成了纳米颗粒、纳米棒、纳米球和纳米板等不同形态的单相Gd2O3纳米结构。采用水热法制备了Gd2O3的一维纳米棒和二维纳米板结构，采用均匀沉淀法制备了三维空心纳米球。研究了Gd2O3纳米颗粒的磁性和磁热性能随温度和场的变化规律。该材料在3-300 K的测量温度范围内表现出典型的顺磁性。磁熵变(−ΔS M)决心从磁等温线以3-38 K温度范围在5 t的最大磁熵变化ΔSMmax值11.2 J公斤−1 K−1 nanoplate, 9.4 J公斤−1 K−1奈米棒,9.2 J公斤−1 K nanosphere−1,和10.7 J公斤−1 K−1纳米样本的观察到温度5 K 5 t的磁场由于大型ΔSMmax,这些Gd2O3纳米结构粒子将被认为是极有前途的低温磁致冷材料。
{"title":"Magnetocaloric properties of shape-dependent nanostructured Gd2O3 oxide particles","authors":"D. Neupane, Jacob Casey, Jolaikha Sultana, A. Pathak, S. Karna, S. Pollard, S. Mishra","doi":"10.1088/2043-6262/ace184","DOIUrl":"https://doi.org/10.1088/2043-6262/ace184","url":null,"abstract":"Single-phase Gd2O3 nanostructures with different morphologies, such as nanoparticles, nanorods, nanospheres, and nanoplates, were synthesised. Gd2O3 1D nanorods and 2D nanoplate architectures were prepared via the hydrothermal method, while 3D hollow nanospheres were synthesised via homogeneous precipitation. The magnetic and magnetocaloric properties of Gd2O3 nanostructured particles were studied as functions of temperature and field. The material demonstrated typical paramagnetic behaviour in the measured temperature range of 3–300 K. The magnetic entropy change (−ΔS M ) was determined from the magnetic isotherms measured in the 3–38 K temperature range in the field up to 5 T. The maximum change in magnetic entropy ΔSMmax value 11.2 J kg−1 K−1 for the nanoplate, 9.4 J kg−1 K−1 for the nanorod, 9.2 J kg−1 K−1 for the nanosphere, and 10.7 J kg−1 K−1 for the nanoparticle sample was observed at temperature 5 K for the magnetic field of 5 T. Owing to large ΔSMmax, these Gd2O3 nanostructured particles would be considered promising materials for magnetic refrigeration at cryogenic temperatures.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43850130","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 : 2023-06-16DOI: 10.1088/2043-6262/acd8b6
Toton Sarkar, Sani Kundu, G. Ghorai, P. Sahoo, A. Bhattacharjee
Zinc oxide nanoparticles (ZnO NPs) were synthesised using Tabernaemontana divaricata flower extract (TFE) in different weight percentages by facile, eco-friendly and cost-effective green synthesis method. Formation and structure of the ZnO NPs were studied by powder XRD, FT−IR, Raman and TEM studies. The crystals formed are of hexagonal wurtzite structure with biological functional groups attached. Average crystallite size of the ZnO NPs (17.5−23.3 nm) was obtained from the analysis of powder XRD data which increased with increase of TFE amount while the estimated values of dislocation density and micro-strain exhibited an opposite behaviour. The optical (direct and indirect) energy band gap values estimated using UV–vis DRS spectral data decreased with increasing amount of TFE. The photoluminescence spectra for the ZnO NPs exhibited multiple peaks spread over the visible region with one peak in the NIR region indicating the existence of various defect levels of Zn and O. Position of these defect levels within the band gap was assigned which is significantly modulated by TFE. TFE amount-dependent peak shift and/or peak broadening were observed in the Raman spectra of the ZnO NPs which were correlated with the growing disorder in the crystals induced by the extract molecules. FESEM study showed the agglomerated NPs with quasi-spherical morphology. Particle size of the ZnO NPs was estimated from FESEM images. EDX study indicated that increased presence of TFE in ZnO decreased the oxygen content in the synthesised material. HRTEM study revealed the agglomeration of nanoparticles with single crystalline nature. Present study convincingly established that flower extract used for the green synthesis efficiently modified the structure and optical property, defect levels and morphology of the potentially useful ZnO nanoparticles.
{"title":"Structural, spectroscopic and morphology studies on green synthesized ZnO nanoparticles","authors":"Toton Sarkar, Sani Kundu, G. Ghorai, P. Sahoo, A. Bhattacharjee","doi":"10.1088/2043-6262/acd8b6","DOIUrl":"https://doi.org/10.1088/2043-6262/acd8b6","url":null,"abstract":"Zinc oxide nanoparticles (ZnO NPs) were synthesised using Tabernaemontana divaricata flower extract (TFE) in different weight percentages by facile, eco-friendly and cost-effective green synthesis method. Formation and structure of the ZnO NPs were studied by powder XRD, FT−IR, Raman and TEM studies. The crystals formed are of hexagonal wurtzite structure with biological functional groups attached. Average crystallite size of the ZnO NPs (17.5−23.3 nm) was obtained from the analysis of powder XRD data which increased with increase of TFE amount while the estimated values of dislocation density and micro-strain exhibited an opposite behaviour. The optical (direct and indirect) energy band gap values estimated using UV–vis DRS spectral data decreased with increasing amount of TFE. The photoluminescence spectra for the ZnO NPs exhibited multiple peaks spread over the visible region with one peak in the NIR region indicating the existence of various defect levels of Zn and O. Position of these defect levels within the band gap was assigned which is significantly modulated by TFE. TFE amount-dependent peak shift and/or peak broadening were observed in the Raman spectra of the ZnO NPs which were correlated with the growing disorder in the crystals induced by the extract molecules. FESEM study showed the agglomerated NPs with quasi-spherical morphology. Particle size of the ZnO NPs was estimated from FESEM images. EDX study indicated that increased presence of TFE in ZnO decreased the oxygen content in the synthesised material. HRTEM study revealed the agglomeration of nanoparticles with single crystalline nature. Present study convincingly established that flower extract used for the green synthesis efficiently modified the structure and optical property, defect levels and morphology of the potentially useful ZnO nanoparticles.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47844577","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 : 2023-06-01DOI: 10.1088/2043-6262/acd8b7
Nguyen Thi Viet Chinh, Dinh Chi Linh, Nguyen Thi Dung, T. D. Thanh
In this work, a sample of Pr0.5Sr0.5MnO3 nanoparticles with an average crystalline size of = 58 ± 2 nm was prepared by a combination of reactive milling method for 6 h at room temperature and heat treatment at the 1100 °C for 0.5 h. The x-ray diffraction analysis revealed the existence of a Pr0.5Sr0.5MnO3 single phase with the tetragonal structure (I4/mcm space group). Temperature and magnetic field dependences of magnetisation measurements indicated a coexistence of two magnetic phase transitions. One is the antiferromagnetic-ferromagnetic transition at T N = 150 K. The other is the second-order ferromagnetic-paramagnetic phase transition at T C = 273.5 K. Using the modified Arrott plots and the Kouvel-Fisher methods, the critical isotherm analysis, and the scaling relation, the magnetic order in Pr0.5Sr0.5MnO3 nanoparticle sample has been pointed out. Accordingly, the critical exponents were found to be β = 0.486, γ = 1.181, and δ = 3.249. These values are quite close to the allowable exponents of the mean field model, suggesting an existence of the long-range ferromagnetic order. A slight deviation from the mean field model has been explained by the formation of the core/shell structure in Pr0.5Sr0.5MnO3 nanoparticle.
{"title":"Structural and critical properties of Pr0.5Sr0.5MnO3 nanoparticle","authors":"Nguyen Thi Viet Chinh, Dinh Chi Linh, Nguyen Thi Dung, T. D. Thanh","doi":"10.1088/2043-6262/acd8b7","DOIUrl":"https://doi.org/10.1088/2043-6262/acd8b7","url":null,"abstract":"In this work, a sample of Pr0.5Sr0.5MnO3 nanoparticles with an average crystalline size of = 58 ± 2 nm was prepared by a combination of reactive milling method for 6 h at room temperature and heat treatment at the 1100 °C for 0.5 h. The x-ray diffraction analysis revealed the existence of a Pr0.5Sr0.5MnO3 single phase with the tetragonal structure (I4/mcm space group). Temperature and magnetic field dependences of magnetisation measurements indicated a coexistence of two magnetic phase transitions. One is the antiferromagnetic-ferromagnetic transition at T N = 150 K. The other is the second-order ferromagnetic-paramagnetic phase transition at T C = 273.5 K. Using the modified Arrott plots and the Kouvel-Fisher methods, the critical isotherm analysis, and the scaling relation, the magnetic order in Pr0.5Sr0.5MnO3 nanoparticle sample has been pointed out. Accordingly, the critical exponents were found to be β = 0.486, γ = 1.181, and δ = 3.249. These values are quite close to the allowable exponents of the mean field model, suggesting an existence of the long-range ferromagnetic order. A slight deviation from the mean field model has been explained by the formation of the core/shell structure in Pr0.5Sr0.5MnO3 nanoparticle.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48896506","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 : 2023-06-01DOI: 10.1088/2043-6262/acd92a
Tran Thi Thu Huong, Nguyên Thİ Hiêp, N. T. Loan, Le Van Long, Hyuksu Han, Nguyen Thi Thao, Ung Thi Dieu Thuy, N. Q. Liem
In this paper, AgInSe2 (AISe) core and AgInSe2/ZnS (AISe/ZnS) core/shell nanocrystals (NCs) were synthesised by a one-pot method in an organic solvent. Firstly, the synthesis of AIS core NCs with different sizes was performed by hot-injection of Se precursor into the Ag and In complexes at different temperatures from 100 °C to 180 °C for a reaction time of 20 min Then, the ZnS was grown on the surface of AISe NCs at 150 °C for 60 min to produce the AISe/ZnS core/shell structures. The as-synthesised AISe core and AISe/ZnS core/shell NCs were characterised by using x-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and optical spectroscopies (UV–vis absorption and photoluminescence (PL)). After shelling ZnS layer, AISe/ZnS core/shell NCs become more stable (12 months) in ambient air and emit strong luminescence with a high quantum yield (QY) of 40% in the range from 610 nm to 762 nm by varying the reaction temperature of AISe core synthesis from 100 °C to 180 °C. The observed increase of QY and blue-shift in photoluminescence spectra after coating ZnS on surface AISe core NCs are rationalised by the formation of the alloyed structure and passivation of surface states. With their outstanding luminescent properties, AISe core and AISe/ZnS core/shell NCs are very promising in designing emitters for solid-state lighting sources in the greenhouse and in-door farming and bio-related devices.
{"title":"Improved stability and luminescent efficiency of AgInSe2 nanocrystals by shelling with ZnS","authors":"Tran Thi Thu Huong, Nguyên Thİ Hiêp, N. T. Loan, Le Van Long, Hyuksu Han, Nguyen Thi Thao, Ung Thi Dieu Thuy, N. Q. Liem","doi":"10.1088/2043-6262/acd92a","DOIUrl":"https://doi.org/10.1088/2043-6262/acd92a","url":null,"abstract":"In this paper, AgInSe2 (AISe) core and AgInSe2/ZnS (AISe/ZnS) core/shell nanocrystals (NCs) were synthesised by a one-pot method in an organic solvent. Firstly, the synthesis of AIS core NCs with different sizes was performed by hot-injection of Se precursor into the Ag and In complexes at different temperatures from 100 °C to 180 °C for a reaction time of 20 min Then, the ZnS was grown on the surface of AISe NCs at 150 °C for 60 min to produce the AISe/ZnS core/shell structures. The as-synthesised AISe core and AISe/ZnS core/shell NCs were characterised by using x-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and optical spectroscopies (UV–vis absorption and photoluminescence (PL)). After shelling ZnS layer, AISe/ZnS core/shell NCs become more stable (12 months) in ambient air and emit strong luminescence with a high quantum yield (QY) of 40% in the range from 610 nm to 762 nm by varying the reaction temperature of AISe core synthesis from 100 °C to 180 °C. The observed increase of QY and blue-shift in photoluminescence spectra after coating ZnS on surface AISe core NCs are rationalised by the formation of the alloyed structure and passivation of surface states. With their outstanding luminescent properties, AISe core and AISe/ZnS core/shell NCs are very promising in designing emitters for solid-state lighting sources in the greenhouse and in-door farming and bio-related devices.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44332634","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 : 2023-06-01DOI: 10.1088/2043-6262/acd92c
K. Shah, M. Parvaiz, G. N. Dar
The recent technological revolution in nanoscience has created a huge potential to build highly sensitive, low-cost and power efficient portable sensors. Here, we have investigated the novel nano-porous penta-graphene nanotube (PGNT) device for detection and separation of halogen gases like fluorine (F2), chlorine (Cl2), bromine (Br2) and iodine (I2). The host carbon atoms are selectively removed to create the nanopores on the tube surface. 1, 2, 3 and 4 host carbon atoms are removed from the surface to create vacancies which were then investigated for detection and separation of halogen gases using functionalisation of pore edges. The I-V measurements were performed to establish the gas detection application of these novel porous structures. Furthermore, interaction energy graphs were obtained which show efficient separation of various halogen molecules by functionalising the pores with F2, Cl2 and H atoms.
{"title":"Porous pentagraphene nanotube halogen gas sensor: a first principles study","authors":"K. Shah, M. Parvaiz, G. N. Dar","doi":"10.1088/2043-6262/acd92c","DOIUrl":"https://doi.org/10.1088/2043-6262/acd92c","url":null,"abstract":"The recent technological revolution in nanoscience has created a huge potential to build highly sensitive, low-cost and power efficient portable sensors. Here, we have investigated the novel nano-porous penta-graphene nanotube (PGNT) device for detection and separation of halogen gases like fluorine (F2), chlorine (Cl2), bromine (Br2) and iodine (I2). The host carbon atoms are selectively removed to create the nanopores on the tube surface. 1, 2, 3 and 4 host carbon atoms are removed from the surface to create vacancies which were then investigated for detection and separation of halogen gases using functionalisation of pore edges. The I-V measurements were performed to establish the gas detection application of these novel porous structures. Furthermore, interaction energy graphs were obtained which show efficient separation of various halogen molecules by functionalising the pores with F2, Cl2 and H atoms.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45341743","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 : 2023-05-31DOI: 10.1088/2043-6262/acd683
Noora Sabah Kamel, K. Aadim, A. Kadhim
This research studied the effects of different laser energies on structural and optical properties. We prepared CdTe thin films by PLD technique using an Nd:YAG laser with a wavelength of 1064 nm and different energies (400, 500, 600, and 700 mJ). The practical experiments were carried out at a temperature of 200 °C. XRD results revealed that all the prepared thin films have polycrystalline structures and cubic systems with average crystalline sizes of 34, 42, 54, and 57 nm for 400, 500, 600, and 700 mJ, respectively. We observed that the optical energy gap of CdTe thin films decreases with the increase of laser energy (1.87–1.58 eV). The topography of the surfaces of CdTe thin films deposited on glass substrates was studied by the AFM technique, and it was shown that the average diameter of all CdTe films increases with increasing laser energies. The mentioned properties were studied for the application of this thin film as the absorber layer in constructing a solar cell.
{"title":"Study of the characterizationn of CdTe thin films prepared by the pulsed laser deposition technique with different laser energies","authors":"Noora Sabah Kamel, K. Aadim, A. Kadhim","doi":"10.1088/2043-6262/acd683","DOIUrl":"https://doi.org/10.1088/2043-6262/acd683","url":null,"abstract":"This research studied the effects of different laser energies on structural and optical properties. We prepared CdTe thin films by PLD technique using an Nd:YAG laser with a wavelength of 1064 nm and different energies (400, 500, 600, and 700 mJ). The practical experiments were carried out at a temperature of 200 °C. XRD results revealed that all the prepared thin films have polycrystalline structures and cubic systems with average crystalline sizes of 34, 42, 54, and 57 nm for 400, 500, 600, and 700 mJ, respectively. We observed that the optical energy gap of CdTe thin films decreases with the increase of laser energy (1.87–1.58 eV). The topography of the surfaces of CdTe thin films deposited on glass substrates was studied by the AFM technique, and it was shown that the average diameter of all CdTe films increases with increasing laser energies. The mentioned properties were studied for the application of this thin film as the absorber layer in constructing a solar cell.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48317994","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 : 2023-05-31DOI: 10.1088/2043-6262/acd6e5
W. Watcharin, S. Gupta, A. Saning, Sireerat Laodheerasiri, L. Chuenchom
Grapefruit peel essential oil exhibited antioxidant and antibacterial activities attributed to their phenolic and flavonoid compounds. In this study, nanoemulsion of grapefruit peel essential oil and carrageenan was investigated for their antioxidant properties. The oil in water (o/w) emulsion was formulated with 0.5% and 1.0% (w/v) grapefruit peel essential oil and carrageenan. Carrageenan was utilised as an encapsulating agent to decrease volatility of essential oil and increase its stability. The resulting nanoemulsion was characterised using transmission electron microscopes (TEM), ultraviolet–visible (UV–vis) spectrophotometry and Fourier-transform infrared spectroscopy (FTIR). Nanoemulsion formulated with 0.5% grapefruit peel essential oil exhibited strong radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) effects showing the highest half maximal effective concentration value (EC50) at 83.4 ± 1.4 mg l−1 and revealed the highest total phenolic content (80.1 ± 11.8 mg GAE/g) in comparison with 1.0% grapefruit peel essential oil-nanoemulsion and free grapefruit peel essential oil (2.0% w/v). The cytotoxicity of nanoemulsion prepared from grapefruit peel essential oil against HeLa cells also exhibited higher than 90% of cell viability, which was not affected by the formulation of nanoemulsion. The incorporation of grapefruit peel essential oil into nanoemulsion improved its stability while retaining its bioactivity and non-toxicity.
{"title":"Free radical scavenging effects of grapefruit essential oil nanoemulsion stabilized with carrageenan and its cytotoxicity assay on HeLa cell line","authors":"W. Watcharin, S. Gupta, A. Saning, Sireerat Laodheerasiri, L. Chuenchom","doi":"10.1088/2043-6262/acd6e5","DOIUrl":"https://doi.org/10.1088/2043-6262/acd6e5","url":null,"abstract":"Grapefruit peel essential oil exhibited antioxidant and antibacterial activities attributed to their phenolic and flavonoid compounds. In this study, nanoemulsion of grapefruit peel essential oil and carrageenan was investigated for their antioxidant properties. The oil in water (o/w) emulsion was formulated with 0.5% and 1.0% (w/v) grapefruit peel essential oil and carrageenan. Carrageenan was utilised as an encapsulating agent to decrease volatility of essential oil and increase its stability. The resulting nanoemulsion was characterised using transmission electron microscopes (TEM), ultraviolet–visible (UV–vis) spectrophotometry and Fourier-transform infrared spectroscopy (FTIR). Nanoemulsion formulated with 0.5% grapefruit peel essential oil exhibited strong radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) effects showing the highest half maximal effective concentration value (EC50) at 83.4 ± 1.4 mg l−1 and revealed the highest total phenolic content (80.1 ± 11.8 mg GAE/g) in comparison with 1.0% grapefruit peel essential oil-nanoemulsion and free grapefruit peel essential oil (2.0% w/v). The cytotoxicity of nanoemulsion prepared from grapefruit peel essential oil against HeLa cells also exhibited higher than 90% of cell viability, which was not affected by the formulation of nanoemulsion. The incorporation of grapefruit peel essential oil into nanoemulsion improved its stability while retaining its bioactivity and non-toxicity.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45561855","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 : 2023-05-26DOI: 10.1088/2043-6262/acd6e4
Peng Cui, Jian Zhang
Co-doping is an effective strategy to optimise the photovoltaic performance of GQDs. However, due to the heterogeneity of GQDs, it is difficult to achieve controllable photovoltaic performance without determining the structure-property relationship. In this work, we perform first-principles calculations to investigate the optoelectronic properties of GQDs doped with S, B, and P atoms. Our results show that S doping is crucial for tuning the photoelectric performance of S,B and S,P co-doped GQDs. Increasing the polarity of the solvent improves the charge transfer performance of single P-doped GQDs. Moreover, single P-doped GQDs show better photovoltaic performance than other doping configurations. Furthermore, the addition of B co-dopants to GQDs with Sh doping configuration improves the energy conversion of GQDs compared to B doping alone. Our study provides guidance for the rational design of GQDs for various photovoltaic applications.
{"title":"Impact of S,B and S,P co-doping on the photovoltaic performance of graphene quantum dots","authors":"Peng Cui, Jian Zhang","doi":"10.1088/2043-6262/acd6e4","DOIUrl":"https://doi.org/10.1088/2043-6262/acd6e4","url":null,"abstract":"Co-doping is an effective strategy to optimise the photovoltaic performance of GQDs. However, due to the heterogeneity of GQDs, it is difficult to achieve controllable photovoltaic performance without determining the structure-property relationship. In this work, we perform first-principles calculations to investigate the optoelectronic properties of GQDs doped with S, B, and P atoms. Our results show that S doping is crucial for tuning the photoelectric performance of S,B and S,P co-doped GQDs. Increasing the polarity of the solvent improves the charge transfer performance of single P-doped GQDs. Moreover, single P-doped GQDs show better photovoltaic performance than other doping configurations. Furthermore, the addition of B co-dopants to GQDs with Sh doping configuration improves the energy conversion of GQDs compared to B doping alone. Our study provides guidance for the rational design of GQDs for various photovoltaic applications.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44348931","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 : 2023-05-25DOI: 10.1088/2043-6262/acd684
S. Rasool, K. Saritha, K. Reddy, M. Tivanov, O. Korolik, V. Gremenok, S. Zimin, I. Amirov
In the present study, the effect of annealing and Ar-plasma treatment on structural, morphological and optical properties of thermally evaporated β-In2S3 thin films has been investigated. During Ar-plasma treatment, some interesting results were observed that an array of metallic indium nanostructures was formed over In2S3 film surface with quasi-spherical or spread droplet shapes of an average size of 20–100 nm in the lateral direction and a height of less than 70 nm. Here, the Ar-plasma treatment serves as a new strategy for the self-formation of metallic indium nanostructures over the film surface. Further, the optical absorption of In2S3 films has been enhanced from 104 to 107 cm−1 while the optical band gap energy decreased from 2.71 eV to 2.50 eV after Ar-plasma treatment. The metallic nanostructures loaded on semiconductor surface can act as an electron trap that can effectively prevent the recombination of photo-generated electron-hole pairs.
{"title":"Effect of Ar-plasma treatment and annealing on thermally evaporated β-In2S3 thin films","authors":"S. Rasool, K. Saritha, K. Reddy, M. Tivanov, O. Korolik, V. Gremenok, S. Zimin, I. Amirov","doi":"10.1088/2043-6262/acd684","DOIUrl":"https://doi.org/10.1088/2043-6262/acd684","url":null,"abstract":"In the present study, the effect of annealing and Ar-plasma treatment on structural, morphological and optical properties of thermally evaporated β-In2S3 thin films has been investigated. During Ar-plasma treatment, some interesting results were observed that an array of metallic indium nanostructures was formed over In2S3 film surface with quasi-spherical or spread droplet shapes of an average size of 20–100 nm in the lateral direction and a height of less than 70 nm. Here, the Ar-plasma treatment serves as a new strategy for the self-formation of metallic indium nanostructures over the film surface. Further, the optical absorption of In2S3 films has been enhanced from 104 to 107 cm−1 while the optical band gap energy decreased from 2.71 eV to 2.50 eV after Ar-plasma treatment. The metallic nanostructures loaded on semiconductor surface can act as an electron trap that can effectively prevent the recombination of photo-generated electron-hole pairs.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46577930","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 : 2023-05-19DOI: 10.1088/2043-6262/acd3e6
M. Joshi, Sukumar Roy, Ayeshvaryaa Tv
In this study, the feasibility of the production of electrospun nanofibre composite mainly for biomedical applications is reported. Biocompatible polyether-based polyurethane, natural proteinaceous polymer silk sericin (SS) and natural inorganic nanoclay halloysite as a drug carrier with a model drug chlorhexidine acetate were used to produce nanofibres by electrospinning technique. Sericin was extracted from Bombyx mori silk cocoons by high pressure high temperature (HT-HP) degumming. Chlorhexidine acetate (CA), an antimicrobial agent, was loaded into halloysite nanotubes (HNTs) at different weight ratios, and 1:1 weight ratio showed the maximum loading which was confirmed by TGA and XRD analysis. Electrospinning of polymer solution with different compositions of polyurethane, sericin, CA and CA-HNTs was conducted at 10% w/v concentration, 20 kV voltage, 15 μl min−1 flow rate and 10 cm distance which resulted in the formation of bead-free uniform fibres. Antimicrobial activity of nanofibrous webs was evaluated by the disc diffusion method (AATCC 90) and it was found that CA and CA-HNT loaded nanofibres show sustained antibacterial action against both the Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. The CA-HNT and sericin/CA-HNT loaded nanofibres showed controlled release of CA. In addition, the cytocompatibility assessment of developed nanofibrous composites showed good biocompatibility. Hence the produced composite nanofibre can serve as an excellent material for sustained drug release for various biomedical applications.
{"title":"Polyurethane/halloysite nano tubes/sericin based electrospun nanocomposite for sustained drug release","authors":"M. Joshi, Sukumar Roy, Ayeshvaryaa Tv","doi":"10.1088/2043-6262/acd3e6","DOIUrl":"https://doi.org/10.1088/2043-6262/acd3e6","url":null,"abstract":"In this study, the feasibility of the production of electrospun nanofibre composite mainly for biomedical applications is reported. Biocompatible polyether-based polyurethane, natural proteinaceous polymer silk sericin (SS) and natural inorganic nanoclay halloysite as a drug carrier with a model drug chlorhexidine acetate were used to produce nanofibres by electrospinning technique. Sericin was extracted from Bombyx mori silk cocoons by high pressure high temperature (HT-HP) degumming. Chlorhexidine acetate (CA), an antimicrobial agent, was loaded into halloysite nanotubes (HNTs) at different weight ratios, and 1:1 weight ratio showed the maximum loading which was confirmed by TGA and XRD analysis. Electrospinning of polymer solution with different compositions of polyurethane, sericin, CA and CA-HNTs was conducted at 10% w/v concentration, 20 kV voltage, 15 μl min−1 flow rate and 10 cm distance which resulted in the formation of bead-free uniform fibres. Antimicrobial activity of nanofibrous webs was evaluated by the disc diffusion method (AATCC 90) and it was found that CA and CA-HNT loaded nanofibres show sustained antibacterial action against both the Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. The CA-HNT and sericin/CA-HNT loaded nanofibres showed controlled release of CA. In addition, the cytocompatibility assessment of developed nanofibrous composites showed good biocompatibility. Hence the produced composite nanofibre can serve as an excellent material for sustained drug release for various biomedical applications.","PeriodicalId":7359,"journal":{"name":"Advances in Natural Sciences: Nanoscience and Nanotechnology","volume":" ","pages":""},"PeriodicalIF":2.1,"publicationDate":"2023-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45635295","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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