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Abstract In this study, pure V6O13 and nickel ion-doped V6O13 powders were synthesized by a simple hydrothermal-calcination method, and their broad-spectrum antimicrobial properties and mechanisms were investigated. The crystal structure, morphology, and chemical state of the powders were thoroughly analyzed by XRD, SEM, TEM, XPS, and UV–Vis. Their antimicrobial properties and mechanisms were evaluated by the ring of inhibition, bio-SEM, live-dead cell staining, ROS detection, and protein leakage experiments. The results showed that nickel ion doping modulated the oxygen defects of V6O13, generating more reactive oxygen species and leading to more severe oxidative stress, resulting in a broad-spectrum and highly efficient antimicrobial effect. This study also revealed the antimicrobial mechanism based on oxygen defect -induced ROS production, which caused cellular oxidative stress damage, leading to leakage of intracellular substances and cell death. This study not only demonstrates the potential of V6O13 as an efficient antimicrobial agent but also provides a strong experimental basis and theoretical support for the engineering design and optimization of novel antimicrobial materials by modulating material defects through ion doping.

A Zn2TiO4 crystalline photovoltaic glass ink was prepared by fast firing at 700 °C for 5 min by the glass crystallisation method, which effectively improved the reflectivity and acid resistance of the photovoltaic glass ink coating. The phase, morphology and properties of the samples were tested by XRD, SEM and UV-vis diffuse reflection, etc. The enhanced reflectivity mechanism was proposed. The results showed that the increase in ZnO/SiO2 ratio reduced the transition temperature (Tg) and crystallisation temperature (Tp) of the glass melt, which could promote the crystallinity of Zn2TiO4 in photovoltaic glass ink coatings and thus improve the acid resistance of photovoltaic glass inks. Significant improvement in reflectance and whiteness is due to the Zn2TiO4 crystallinity growth, which fills in the pores of the ink surface, and TiO2 fillers keep almost the same surface roughness (0.2 µm) and wetting angle (5.2°). Typical samples achieved 89.2% of the whiteness and 88.0% of the reflectance, and the weight loss in acid was 3.9 mg/cm2, which could improve the efficiency of solar power generation.

The emergence of drug resistance due to the overuse of antibiotics has made the prevention and treatment of invasive fungal infections caused by Candida albicans (C. albicans) a great challenge. Oxygen vacancy-rich inorganic materials show great promise in the antimicrobial field due to their unique physicochemical properties. Defect engineering can significantly optimize the electronic structure of inorganic materials to further enhance their antimicrobial activity. We designed oxygen vacancy defect-rich V6O13 powders using the hydrothermal-calcination method and investigated their anti-C. albicans activity. The results showed that the stronger antibacterial activity is attributed to the fact that the optimized V6O13 powder oxygen vacancy defects induced a reduction reaction of dissolved oxygen in the environment, which produced ROS with strong oxidative properties, causing damage to the wall membrane of C. albicans and leakage of intracellular material. The minimum inhibitory concentration (99% or more inhibition) of V6O13 powders is 4 mg/mL. This work not only provides a facile method for constructing oxygen-rich vacancies in V6O13 powders, but also provides new insights into the potential of inorganic materials optimized by defect engineering for efficient antimicrobial activity.

The rapid development of solar energy technology has led to significant progress in recent years, but the daily maintenance of solar panels faces significant challenges. The diagnosis of solar panel failures by infrared detection devices can improve the efficiency of maintenance personnel. Currently, due to the scarcity of infrared solar panel failure samples and the problem of unclear image effective features, traditional deep neural network models can easily encounter overfitting and poor generalization performance under small sample conditions. To address these problems, this paper proposes a solar panel failure diagnosis method based on an improved Siamese network. Firstly, two types of solar panel samples of the same category are constructed. Secondly, the images of the samples are input into the feature model combining convolution, adaptive coordinate attention (ACA), and the feature fusion module (FFM) to extract features, learning the similarities between different types of solar panel samples. Finally, the trained model is used to determine the similarity of the input solar image, obtaining the failure diagnosis results. In this case, adaptive coordinate attention can effectively obtain interested effective feature information, and the feature fusion module can integrate the different effective information obtained, further enriching the feature information. The ACA-FFM Siamese network method can alleviate the problem of insufficient sample quantity and effectively improve the classification accuracy, achieving a classification accuracy rate of 83.9% on an open-accessed infrared failure dataset with high similarity.

In this study, the Mg2+-doped anatase TiO2 phase was synthesized via the solvothermal method by changing the ratio of deionized water and absolute ethanol Vwater/Vethanol). This enhances the bleaching efficiency under visible light. The crystal structure, morphology, and photocatalytic properties of Mg-doped TiO2 were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, N2 adsorption-desorption, UV-Vis spectroscopy analysis, etc. Results showed that the photocatalytic activity of the Mg2+-doped TiO2 sample was effectively improved, and the morphology, specific surface area, and porosity of TiO2 could be controlled by Vwater/Vethanol. Compared with the Mg-undoped TiO2 sample, Mg-doped TiO2 samples have higher photocatalytic properties due to pure anatase phase formation. The Mg-doped TiO2 sample was synthesized at Vwater/Vethanol of 12.5:2.5, which has the highest bleaching rate of 99.5% for the rhodamine B dye during 80 min under visible light. Adding Mg2+-doped TiO2 into the phase-separated glaze is an essential factor for enhancing the self-cleaning capability. The glaze samples fired at 1180 °C achieved a water contact angle of 5.623° at room temperature and had high stain resistance (the blot floats as a whole after meeting the water).

Environmental deterioration has put higher requirements on the acid resistance of automotive glass enamel. The present paper aims to prepare acid-resistant glass-ceramics used in automobile glass enamel. Base glasses with the compositions 15R2O-xBi2O3-10B2O3-(75-x) SiO2 (R2O is a mixture of Li2O, Na2O, and K2O (1:1:1, molar ratio), where x = 10, 15, 20, 25, and 30, respectively) was prepared by the melt-quenching method, and glass-ceramics were prepared by their controlling crystallization heat treatment. Crystallization behavior and crystallization ability of base glasses were investigated using the thermal stability parameter (S), the crystallization kinetics calculation results of base glasses, as well as the phase identification results of the heat-treated samples. The effects of the heat treatment temperature on the micromorphology and acid resistance of the heat-treated glasses were also investigated. Then, the optimized glass ceramic was used to prepare automotive glass enamel. The results indicate that: (I) with the increase of Bi2O3/SiO2 ratio, the characteristic temperature of the base glass decreases, the coefficient of thermal expansion (CTE) and crystallization ability increases significantly, the crystallization temperature range becomes wider; (II) the crystallization activation energy of base glasses are in the range of 169~264 kJ/mol; (III) Bi2SiO5 and Bi2O2SiO3 metastable phases are mainly precipitated when the crystallization temperature is between 530 °C and 650 °C, while only Bi4Si3O12 phase is precipitated when the crystallization temperature is above 650 °C; (IV) crystallinity of base glass increases significantly with increasing heat treatment temperature, which is beneficial to improve the acid resistance of heat treated products; (V) automotive glass enamel was prepared by mixing 15R2O-25Bi2O3-10B2O3-50SiO2 glass-ceramic powder with copper-chrome black and varnish, and then printed on the automobile glass substrate. All the properties of the sintered enamel can meet the market requirements, and the acid resistance of our product is better than that of market products.

Calcium titanate (CaTiO3) with prism-like-shaped and CaTi2O4(OH)2 nanosheet-like morphology were synthesized by a simple solvothermal route without any surfactants. X–ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR) were employed to investigate the microstructure of the samples. The experimental results showed that NaOH concentration played a key role for the formation of CaTiO3 prisms. With increasing NaOH concentrations, the obtained sample changed from CaTi2O5 aggregated particles to CaTi2O4(OH)2 nanosheets, and then to CaTiO3 prisms. When NaOH concentration was 7 M, CaTiO3 morphology is mainly composed of regular prisms. A rational mechanism was proposed to illustrate the morphology evolution of the samples synthesized at various NaOH concentrations. And the CaTi2O4(OH)2 interlaminar structure was illustrated.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9697

Calcium titanate (CaTiO3) with prism-like-shaped and CaTi2O4(OH)2 nanosheet-like morphology were synthesized by a simple solvothermal route without any surfactants. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR) were employed to investigate the microstructure of the samples. The experimental results showed that NaOH concentration played a key role for the formation of CaTiO3 prisms. With increasing NaOH concentrations, the obtained sample changed from CaTi2O5 aggregated particles to CaTi2O4(OH)2 nanosheets, and then to CaTiO3 prisms. When NaOH concentration was 7 M, CaTiO3 morphology is mainly composed of regular prisms. A rational mechanism was proposed to illustrate the morphology evolution of the samples synthesized at various NaOH concentrations. And the CaTi2O4(OH)2 interlaminar structure was illustrated. [ABSTRACT FROM AUTHOR]