Plants are one of the best sources to obtain a variety of natural surfactants in the field of green synthesizing material. Sambucus ebulus, which has unique natural properties, has been considered a promising material in traditional Asian medicine. In this context, zinc oxide nanoparticles (ZnO NPs) were prepared using S. ebulus leaf extract, and their physicochemical properties were investigated. X-ray diffraction (XRD) results revealed that the prepared ZnO NPs are highly crystalline, having a wurtzite crystal structure. The average crystallite size of prepared NPs was around 17 nm. Green synthesized NPs showed excellent absorption in the UV region as well as strong yellow-orange emission at room temperature. Prepared nanoparticles exhibited good antibacterial activity against various organisms and a passable photocatalytic degradation of methylene blue dye pollutants. The obtained results demonstrated that the biosynthesized ZnO NPs reveal interesting characteristics for various potential applications in the future.

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Cross-point array (CPA) structure memories using a memristor are attracting a great deal of attention due to their high density integration with a 4F2 cell. However, a common significant drawback of the CPA configuration is crosstalk between cells. To date, the CPA structure using a redox-based memristor has restrictions to minimize the operating current level due to their resistive switching mechanism. This study demonstrates suitable characteristics of a ferroelectric tunnel junction (FTJ) for the memristor of the CPA structure using an electrostatic model. From the FTJ of the Au/p-type Pr0.98Ca0.02MnO3 (4 nm)/BaTiO3 (4.3 nm)/n-type Ca0.98Pr0.02MnO3 (3 nm)/Pt(111) structure, which has a higher and thicker potential barrier, a good memristive effect for the CPA structure with a high nonlinear current-voltage curve and low current operation, was obtained by Δ Fowler-Nordheim tunneling with effectively blocked direct tunneling and thermionic emission. The FTJ demonstrated reduced sneak current and the possible for high nonlinearity.

Zinc oxide nanocrystals (ZnO NCs) were synthesized via a sol−gel method. After the synthesis, their surface was modified using 2,2,2-trifluoroacetic acid followed by ultraviolet (UV) treatment of the resulting fluorinated ZnO (F-ZnO) NC thin films. The chemical bonding therein and their structural and electrical properties were investigated. Moreover, the oxygen vacancy and electroluminescence properties of the densified ZnO NCs were evaluated. The effects of both UV treatment and fluorination on the morphological and electrical characteristics of the F-ZnO NC thin films were established. Based on the results, the ligand on the NCs was decomposed, and the thin film was densified. The mobility of the UV-treated F-ZnO NC thin film, which is 20.48 cm 2 •V −1 •s −1 , is four orders higher than the pristine ZnO NC thin film. By UV irradiation, the recombination of oxygen vacancies in ZnO was controlled. With the oxygen vacancies decreased, the core electroluminescence of ZnO was enhanced and the band gap of the ZnO NCs was widened from 3.25 to 3.51 eV. Therefore, the core electroluminescence of ZnO was enhanced while the interlayer emission was decreased for quantum-dot lightemitting device applications.

Zinc oxide (ZnO) nanocrystals (NCs) were synthesized using a modified sol-gel method. Ultraviolet (UV) treatment was performed under various atmospheres on the highly stacked ZnO NCs. The prepared NCs were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, photoluminescence spectroscopy, and atomic force microscopy to investigate their structural, electrical, and electrochemical properties. Through these analyses, the effect of the UV treatment on the chemical and electrical characteristics of ZnO NCs was established. According to the analyses, the organic ligands in the NCs were decomposed, and the particles were densified. The mobility of UV-treated ZnO NCs thin films increased to 1.4 cm 2 /Vs, almost 2 orders higher than the UV untreated ZnO thin films. It was confirmed that the recombination from oxygen vacancies of ZnO could be controlled by UV irradiation. As decreased oxygen vacancies, the band gap of ZnO NCs was increased from 3.2 eV to 3.27 eV.

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