International Journal of Nanoscience

The main objective of this work was to study the synthesis and characteristics of two-dimensional heterostructures (2D/2D) using pure molybdenum disulfide (MoS${}_2)$ and doped with phosphorus at 5% and 15% combined with graphene oxide (GO) and graphene monolayer. These were deposited on silicon and copper substrates using two different deposition methods: Microdrop casting and chemical vapor deposition. Chemical and structural information of the samples were characterized by Raman spectroscopy, Energy Dispersion X-ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM) and Kelvin Probe Force Microscopy (KPFM). The results prove the synergy between the materials resulting in electronic coupling, making this system potential for applications in electronic devices such as sensors, resistors and capacitors.

Latent fingerprint detection and visualization remains a challenge especially where problems of poor contrast, auto-fluorescent surfaces and patterned backgrounds are encountered. As a result there is an increasing interest in the development of simple, cost effective, rapid and yet accurate methods for latent fingerprint detection and recovery. Herein, this paper reports the synthesis of bright blue photoluminescent carbon dots (C-dots) via an eco-friendly and simple one-step microwave-assisted carbonization of potato peels’ biomass. The C-dots were prepared in only 3 min and ground into powder and used without any further treatment. The as-prepared C-dots were characterized using atomic force microscope, Fourier transform infra-red spectroscopy and X-ray diffraction with an average size of 1.0nm. The optical properties of the as-prepared C-dots were studied by UV-Vis spectroscopy and spectrofluorometer which established an excitation and emission wavelengths of 390nm and 480nm, respectively. Owing to their strong solid state fluorescence, the as-prepared C-dots’ powder was successfully used in latent fingerprint detection and imaging on porous and nonporous surfaces. Latent fingerprints were recovered with high resolution and excellent quality providing sufficient details for individual identification. These findings demonstrate that C-dots derived from biomass have a great potential in latent fingerprint analysis for forensic applications.

In this study, Myrtus communis was used for the bioproduction of colloidal silver nanoparticles (AgNPs). The resultant AgNPs were characterized by X-ray diffraction (XRD), UV-Visible spectroscopy and field-emission scanning electron microscopy (FESEM). The hump-like peaks were recorded near the wavenumber 422 nm and such peaks originated due to the electronic structures of silver tiny particles and silver nanoparticles. The four intensive peaks of XRD patterns indicated the crystalline nature and the face-centered cubic structure of the AgNPs. The average crystallite size of the AgNPs ranged from 19nm to 25nm. The FESEM image illustrates the good dispersion of the AgNPs and the spherical shape of the nanoparticles. The AgNPs were prepared to study antifungal activity against plant pathogenic fungi Aspergillus niger, Rhizopus stolonifer and Neurospora crassain vitro. Results showed that the AgNPs demonstrated high antifungal activity against these fungi with significant differences between treatments when compared with the control (without nanoparticles).

In this paper, the effect of hydrogen embrittlement in High-strength low-alloy steel (HSLA) material was studied. HSLA steels are known for their susceptibility to hydrogen induced failure especially when subjected to hydrogen rich environment. In this research, samples from HSLAS were surface-treated using chemical vapor deposition (CVD) techniques, followed by direct Zinc coating using physical vapor deposition (PVD). Other samples were additionally post-heat treated at a temperature of 260^∘C for 4h to optimize the coating process. The hydrogen embrittlement test was performed by immersing the tensile samples in a solution containing H₂SO₄ diluted with water for 24h. Hardness, and mechanical properties were evaluated using tensile testing. XRD and SEM were used for microstructural and topographical features’ examination of the treated samples. The results indicate that the samples of combined $\mathrm{\text{PVD}}+\mathrm{\text{CVD}}$ coating that was backed at 260^∘C show superior resistance to hydrogen embrittlement compared to other conditions. This could be attributed to the buildup of a strong outer layer that prevents hydrogen from diffusing towards the base HSLAS material. The greater mechanical properties are possibly due to the reduction of hydrogen amount generated by the surface reaction associated by the formation of Zn(N${}_3{)}_2$ phase and the reduction of hydrogen amount passed through Zn and C₃N₄ layers.

In the multicolor regulation of visible-light band, the inorganic electrochromic multicolor modulation has always been the bottleneck of expanding the application of inorganic electrochromic reflection display. An electrochromic device (ECD) based on an ultracompact unsymmetric Fabry–Perot resonator was designed. Electrochromic oxides such as tungsten oxide, offer the possibility to tune their refractive index and extinction coefficient upon ion insertion, allowing active control over resonance conditions for Fabry–Perot cavity-type devices. The spectrum colors of red, yellow, green and blue can be obtained by adjusting the thickness of tungsten oxide in the W/(WO${}_{3-x}\cdot \mathit{\text{n}}$H₂O) electrode. The optical constants of tungsten oxide can be adjusted reversibly by using electrochemical ion insertion/stripping, and the reflection peak of W/(WO${}_{3-x}\cdot n$H₂O) electrode in the visible-light band can be adjusted. The dynamic color control of the ECDs can be achieved finely.

The most serious public health problems now involve antibiotic resistance and cancer that kills more than 15 million people per year which indicates that the existing antibiotics and chemotherapy are not as active as before. This paper provides nanotechnology as a possible answer. However, typical physicochemical nanomaterials production processes, frequently requiring the use of harmful catalysts, have environmental or social implications. This paper covers how to use the innovative liquid-pulsed laser ablation (LP-PLA) process to manufacture selenium nanoparticles (SeNPs). After the first set of radiation at 500mJ laser energy and 100 pulses, a second set was employed to decrease the size to less than 100nm with the same condition. Therefore, two main groups of 80 and 10nm had colloidal solutions for spherical SeNPs. The particles were also more stable following the second round of irradiation. Furthermore, when SeNPs were grown with human dermal fibroblast cells at doses up to 1ppm, they had a mild cytotoxic impact. The potential of utilizing totally naked SeNPs produced using the novel LP-PLA procedure as a novel and efficient way of producing nanoparticles for biomedical applications is presented in this paper.

In this paper, a modified seed-mediated growth approach to produce gold nanoparticles through HAuCl₄ chemical reduction in water fabricated by growth process on indium tin oxide (ITO) was proposed. Particular attention was devoted to exploring the seeding and growth number cycle process in the formation of Au nanoparticles on the ITO surface. In agreement with the assumed analytical model, we have found that the absorbance maximum intensity ${\lambda }_{\mathrm{\text{max}}}$ depends substantially on the metal nanoparticles’ sizes, shape and density on the ITO surface. The deposited nanoparticles’ synthesized parameters were evaluated by the surface images obtained using field emission scanning electron microscopy (FE-SEM), UV-Vis spectroscopy and electrochemical measurements. The results show that the electrochemical responses of the as-prepared sample were significantly improved, in particular for the 2-cycle seeded particles followed by one-cycle growth.

This paper presents a single-ended Schmitt Trigger-based 9T SRAM cell, significantly improving thermal stability for real-time memory applications on a chip operated in a high radiation environment. The proposed single-ended 9T-ST SRAM cell has 73% and 13% improvement in read stability, 42% and 13% improvement in hold stability from 6T and 10T SRAM cells, respectively. The read stability of the proposed SRAM cell is compared with the conventional 6T SRAM cell, which is designed and tested for 23000 MC simulation samples to protect it from read failure. During read operation, the impact of temperature variation on the performance of memory cells is observed using Monte Carlo simulation for a temperature change from 20^∘C to 60^∘C, as 5%, 32%, and 48% variation in RSNM for 9T-ST, 10T-ST, and 6T SRAM cells, respectively. The proposed SRAM cell is designed and verified in the Synopsys Custom compiler.

New hybrid (organic–inorganic) material based on nanocrystalline CdSe capped with EDTA and poly(O-toluidine) doped with camphor sulfonic acid (POT-CSA) is processed from solution and characterized in order to relate the device function (optical absorption, charge separation and transport properties) to active-layer properties and device parameters. POT/CdSe hybrid material has been synthesized using physical mixing method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) are used to investigate the structural and morphological properties. The organic–inorganic composite system was applied as an active device component to demonstrate the electrical memory effects. The device exhibited a nonvolatile, resistive switching performance with a constant ON–OFF current ratio. The nonvolatile behavior was confirmed by applying a 2.5-V read pulse.

In this study, a novel medicinal plant, Lagerstroemia indica, was used to extract Silver Oxide Nanoparticles (Ag₂O-NPs) and the in vitro anticancer potentials of synthesized Ag₂O-NPs were evaluated on human cancer cell lines. Ultraviolet–Visible (UV-Vis) spectroscopy confirmed the formation of Ag₂O and the particle size of 9.98nm was confirmed by X-Ray Diffraction (XRD) analysis. Scanning Electron Microscope (SEM) images showed spherical-shaped NPs. The anticancer potential determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay showed significant cytotoxic potential against breast cancer (MCF-7) and cervical cancer (HeLa) cell lines with the IC50 concentrations at 46.22$\mu$g/ml and 39.39$\mu$g/ml, respectively. Ag₂O-NPs showed a subsequent reduction in Mitochondrial Membrane Potential (MMP) and increased level of Reactive Oxygen Species (ROS). The dual staining of Ag₂O-NPs showed a greater number of early apoptotic and late apoptotic cells as compared to the standard drug camptothecin. Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) determined an upregulated level of Caspase3 and p53. Thus, the present study indicates that Ag₂O-NPs synthesized from L. indica may be used as an anti-cancer drug after further in vivo trials.