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The energy storage capacity of a material is primarily influenced by its specific capacitance. A series of MnxNi1-xCo2O4 at x = 0.0 – 0.10 with Δx = 0.02 was prepared using the low-temperature microwave hydrothermal (M-H) method at 160 °C, and the synthesised samples were sintered at 750 °C for 4 h. The samples were characterised by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) analysis. It is observed from X-ray diffraction that all the samples have a cubic topology belonging to the space group Fd-3m, and the average lattice constant varies from 8.049 to 8.074. The average grain size of all samples is in the range of 96 nm to 326 nm. The valence states of Mn2+, Mn3+, Ni2+, Ni3+, Co2+, and Co3+ were confirmed by X-ray photoelectron spectroscopy. The electrochemical studies using CV, GCD, and EIS were performed on all the samples. A high specific capacitance (Csp) of 490 F g−1 and high energy density and power density were reported for Mn0.06Ni0.94Co2O4, showing good electrochemical properties that are useful for supercapacitor applications. Highlights: Series of MnNCO synthesized by Microwave hydrothermal method. The average grain size is in the range of 96–326 nm. The highest Porosity of 31.17 nm is found for sample Mn0.06Ni0.94Co2O4. Higher pore size ensures more specific capacitance for the sample, x = 0.06. [ABSTRACT FROM AUTHOR]

The present study reports the green synthesis of cupric oxide nanoparticles (CuO NPs) by an aqueous leaf extract of Moringa oleifera and the antifungal activity assessment of CuO NPs against the phytopathogenic fungi Aspergillus flavus and Aspergillus niger. The CuO NPs showed variable fungitoxic effects against A. flavus and A. niger. At higher doses (1 mg/mL), 83.51 % of mycelial inhibition was found against A. flavus, but 43.51 % was found against A. niger. The percentage inhibition of mycelial growth was found to be dose dependent. The cell viability analysis was carried out to reveal the mechanism of the fungitoxic effect of synthesized NPs and it was revealed that the CuO NPs caused oxidative stress associated with increased ROS production, leading to fungal cell death. The synthesized CuO NPs showed single phase cupric oxide with a monoclinic structure and highly uniform in size (3–5 nm). As the synthesized CuO NPs showed good stability under open atmospheric conditions and a fungitoxicity effect against A. flavus, they may be used to control fungal diseases in an eco‐friendly manner. [ABSTRACT FROM AUTHOR]

SrCrFeO ( x = 0.0, 0.1, 0.3, 0.5, 0.7, 0.9) hexaferrites were prepared by a microwave-hydrothermal method and subsequently sintered at 950°C for 90 min using the microwave sintering method. The results show that, with increasing Cr content, the lattice parameters changed anisotropically. The average grain sizes of sintered samples were in the range of 280 nm to 660 nm. The saturation magnetization systematically decreased with increasing Cr doping, but the coercivity values increased. The electrical resistivity (log ρ) decreased linearly with increasing temperature up to a certain temperature known as the transition temperature ( T), and T decreased with further increase ( x > 0.5) of the Cr content. This decrease in log ρ and the activation energy ( E) is due to electron hopping and occupancy of doped ions at different lattice sites. We found that the dielectric constant and dielectric loss for all the samples decreased with the Cr content. The structural, magnetic, and electrical properties of Cr-doped SrFeO hexaferrites have thus been investigated. [ABSTRACT FROM AUTHOR]

We investigated the anisotropic magnetoresistance (AMR) effects for La0.67(Ca1-xSrx)0.33MnO3 films epitaxially grown on (001) oriented SrTiO3 substrates. The increase of Sr doping gives rise to the enhancement of the metal-insulator transition temperature, but suppresses the AMR amplitude. The dependence of AMR on the magnetic field orientation for the Sr doping samples shows the coexistence of two-fold and four-fold symmetries, which is changed with varying the temperature. Moreover, the sign of AMR is changed from negative to positive with increasing the temperature. The abnormal AMR behaviors can be understood by different s-d scattering occurring at different temperatures. [ABSTRACT FROM AUTHOR]