Textiles functionalized with zno nanoparticles obtained by chemical and green synthesis protocols: evaluation of the type of textile and resistance to uv radiation

The study evaluates five types of commercial textiles with different cotton and polyester contents widely used in the garment industry. These textile samples have been subjected to treatment by the exhaustion method using zinc oxide nanoparticles (NP ZnO) (textile functionalization) with the aim of improving their efficiency in blocking UV radiation. The ZnO nanoparticles have been obtained by two methods: The green or also called biosynthesis (using the extract of Coriandrum sativum as an organic reducing agent), and the chemical method (using NaOH as an inorganic reducing agent). The results related to the green method show having achieved a defined geometric configuration with an average size of 97.77 nm (SD: 9.53). On the contrary, the nanostructures obtained by the chemical method show pentagonal configurations with average sizes of 113 nm (SD: 6.72). The textiles functionalized with

Influence of operating temperature on the activation efficiency of Li-ion cells with xLi2MnO3-(1-x)LiMn0.5Ni0.5O2 electrodes

In this study, the effect of operating temperature at 55 °C on xLi2MnO3-(1-x)LiMn0.5Ni0.5O2 electrodes during the charge/discharge process at different current densities was investigated. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used for structural and morphological analysis of the fabricated cathode materials, while charge-discharge curves and differential capacity were used to study the electrochemical behavior. Results confirm the formation of the structures with two phases associated with the components of the layered material. It was found that at 55 °C, a capacity higher than 357 mAh g-1 could be achieved at a voltage of 2.5-4.8 V vs. Li/Li+, which was larger than the capacity achieved at room temperature. At 55 °C, a change in valence could be observed during charging and discharging due to the change in the position of the peaks associated with Mn and Ni, highlighting cathodic material with x = 0.5 as the material that retains the layered structure at this temperature. This work confirms the good performance of electrodes made with this material at elevated temperatures and gives a better understanding of its electrochemical behavior

Effect of x on the Electrochemical Performance of Two-Layered Cathode Materials xLi2MnO3–(1−x)LiNi0.5Mn0.5O2

In our study, the cathodic material xLi2MnO3–(1−x)LiNi0.5Mn0.5O2 was synthesized by means of the co-precipitation technique. The effect of x (proportion of components Li2MnO3 and LiNi0.5Mn0.5O2) on the structural, morphological, and electrochemical performance of the material was evaluated. Materials were structurally characterized using X-ray diffraction (XRD), and the morphological analysis was performed using the scanning electron microscopy (SEM) technique, while charge–discharge curves and differential capacity and impedance spectroscopy (EIS) were used to study the electrochemical behavior. The results confirm the formation of the structures with two phases corresponding to the rhombohedral space group R3m and the monoclinic space group C2/m, which was associated to the components of the layered material. Very dense agglomerations of particles between 10 and 20 µm were also observed. In addition, the increase in the proportion of the LiNi0.5Mn0.5O2 component affected the initial irreversible capacity and the Li2MnO3 layer’s activation and cycling performance, suggesting an optimal chemical ratio of the material’s component layers to ensure high energy density and long-term durability

Evaluation of the antiviral activity of ultraviolet light and zinc oxide nanoparticles on textile products exposed to Avian coronavirus

This research has developed a piece of sanitizing locker-model equipment for textiles exposed to avian coronavirus, which has been put under the influence of UV light, UV + zinc oxide nanoparticles (phytosynthesized ZnONP), and water + UV, and, in turn, under the influence of the exposure time (60, 120, 180 s). The results linked to the phytosynthesis of ZnONP indicate a novel method of fabricating nanostructured material, nanoparticles with spherical morphology and an average size of 30 nm. The assays were made based on the viral viability of avian coronavirus according to the mortality of SPF embryonated eggs and a Real-Time PCR for viral load estimation. This was a model to evaluate the sanitizing effects against coronaviruses since they share a very similar structure and chemistry with SAR-CoV-2. The influence of the type of textile treatment evidenced the potential effect of the sanitizing UV light, which achieved 100% of embryo viability. The response of the ZnONP + UV nebulization showed a notorious influence of photoactivation according to the exposure time, and the 60-s treatment achieved a decrease of 88.9% in viral viability, compared to 77.8% and 55.6% corresponding to the 120 and 180-s treatments, respectively. Regarding the decrease in viral load between the types of treatments, UV 180 s reduced 98.42% and UV 60 s + ZnONP reduced 99.46%, respectively. The results show the combinatorial effect of UV light and zinc nanoparticles in decreasing the viral viability of avian coronavirus, as a model of other important coronaviruses in public health such as SARS-CoV-2

Cu2O nanoparticles synthesized by green and chemical routes, and evaluation of their antibacterial and antifungal effect on functionalized textiles

The potential for the application of metal-containing nanomaterials at the nanoscale promotes the opportunity to search for new methods for their elaboration, with special attention to those sustainable methods. In response to these challenges, we have investigated a new method for green synthesis of cuprous oxide nanoparticles (Cu2O NPs) using Myrciaria dubia juice as an organic reductant and, comparing it with chemical synthesis, evaluating in both cases the influence of the volume of the organic (juice) and chemical (ascorbic acid) reductants, for which a large number of techniques such as spectrophotometry, EDX spectrometry, TEM, SEM, DLS, FTIR spectroscopy have been used. Likewise, the nanomaterial with better morphological characteristics, stability, and size homogeneity has been applied in the functionalization of textiles by means of in situ and post-synthesis impregnation methods. The success of the synthesis process has been demonstrated by the antimicrobial activity (bacteria and fungi) of textiles impregnated with Cu2O NPs

Biogenic production of silver, zinc oxide, and cuprous oxide nanoparticles, and their impregnation into textiles with antiviral activity against SARS-CoV-2

Nanotechnology is being used to fight off infections caused by viruses, and one of the most outstanding nanotechnological uses is the design of protective barriers made of textiles functionalized with antimicrobial agents, with the challenge of combating the SARS-CoV-2 virus, the causal agent of COVID-19. This research is framed within two fundamental aspects: the first one is linked to the proposal of new methods of biogenic synthesis of silver, cuprous oxide, and zinc oxide nanoparticles using organic extracts as reducing agents. The second one is the application of nanomaterials in the impregnation (functionalization) of textiles based on methods called "in situ" (within the synthesis), and "post-synthesis" (after the synthesis), with subsequent evaluation of their effectiveness in reducing the viral load of SARS-CoV-2. The results show that stable, monodisperse nanoparticles with defined geometry can be obtained. Likewise, the "in situ" impregnation method emerges as the best way to adhere nanoparticles. The results of viral load reduction show that 'in situ' textiles with Cu2O NP achieved a 99.79% load reduction of the SARS-CoV-2 virus

Influencia de la ferrita de cobalto en la propiedades magnetoeléctricas de las películas delgadas de ferrita de bismuto depositadas por spin coating

Las películas de (1-x) BiFeO3- (x) CoFe2O4 variando la concentración (x = 0, 0.1, 0.2 y 0.3), fueron depositadas por spin coating sobre sustratos de Pt (Pt/TiO2/SiO2/Si) a partir de soluciones precursoras con una concentración de 0.05 molar, la cual fue obtenida por sol-gel. En la caracterización de las películas delgadas se estudió la estructura y las propiedades magnetoeléctricas mediante difracción de rayos X, corriente de fuga, constante dieléctrica, curva de histéresis ferroeléctrica y ferromagnética. En el difractograma de rayos X se muestran picos característicos con la formación de BiFeO3 y el crecimiento de los picos pertenecientes al CoFe2O4 con el aumento de x. Todas las muestras revelan poca corriente de fuga, siendo la menor de 10-10 A / cm2 para (0.8) BiFeO3- (0.2) CoFe2O4.  La constante dieléctrica se incrementó en el rango de 102Hz a 105Hz luego disminuyó debido a la relajación dieléctrica, para todas las muestras la pérdida dieléctrica es menor al 4%. Todas las películas muestran polarización y magnetización remanentes mayores a 60 μC/cm2 y 30 emu/gr  respectivamente.  Palabras clave: magnetoeléctricas, películas, ferromagnética  y ferroeléctrica

Textiles Functionalized with ZnO Nanoparticles Obtained by Chemical and Green Synthesis Protocols: Evaluation of the Type of Textile and Resistance to UV Radiation

The study evaluates five types of commercial textiles with different cotton and polyester contents widely used in the garment industry. These textile samples have been subjected to treatment by the exhaustion method using zinc oxide nanoparticles (NP ZnO) (textile functionalization) with the aim of improving their efficiency in blocking UV radiation. The ZnO nanoparticles have been obtained by two methods: The green or also called biosynthesis (using the extract of Coriandrum sativum as an organic reducing agent), and the chemical method (using NaOH as an inorganic reducing agent). The results related to the green method show having achieved a defined geometric configuration with an average size of 97.77 nm (SD: 9.53). On the contrary, the nanostructures obtained by the chemical method show pentagonal configurations with average sizes of 113 nm (SD: 6.72). The textiles functionalized with NP ZnO obtained by biosynthesis showed a better efficiency in blocking ultraviolet radiation (UV)

Silver nanoparticles: Stimulation by radiation in the visible spectrum and its influence on stability [Nanopartículas de plata: Estímulo por radiación en el espectro visible y su influencia en la estabilidad]

RESUMEN El objetivo del estudio fue evaluar el efecto en la estabilidad de las nanopartículas de plata sintetizadas por ruta química, como función de la variación del tiempo de exposición de la intensidad luminosa. Se evaluaron por espectrofotometría UV-Vis dos casos, el primero para solución coloidal, el cual mostró tener su pico de absorbancia en 434 nm, típico en nanopartículas de plata con morfología esférica; en un segundo caso para solución coloidal bajo exposición de intensidad luminosa constante (4409 lux) con tiempos que van desde 15 horas hasta 48 horas. Los resultados sugieren el incremento del diámetro de las nanoesferas en función al incremento del tiempo de exposición luminosa, así como un aumento de la absorbancia, lo que indica una posible reacción incompleta y una mayor producción.ABSTRACT The objective of the study was to evaluate the effect on the stability of the silver nanoparticles synthesized by chemical route, according to the variation of the time of exposure of the luminous intensity. Two cases were evaluated by UV-Vis spectrophotometry, the first for colloidal solution, which showed its absorbance peak at 434 nm, typical for silver nanoparticles with spherical morphology; in a second case for colloidal solution under constant light intensity exposure (4409 lux) with times ranging from 15 hours to 48 hours. The results suggest the increase of the diameter of the nanospheres as a function of the increase of time luminous exposition, alsos an increase of the absorbance, which indicates a possible incomplete reaction and a greater production

Effect of time on the reducing capacity of wine residue extracts: Applicability in the biosynthesis of silver nanoparticles [Efecto del tiempo en la capacidad reductora de extractos de residuos vinícolas: Aplicabilidad en la biosíntesis de nanopartículas de plata]

RESUMEN En el sector agroindustrial la materia prima es sometida a procesos de transformación para otorgarle un valor agregado, para ello se implementa diversas metodologías las cuales facilitan sus consumos, pero los residuos vinícolas por el contrario generan una de las principales problemáticas ambientales. Esta investigación adopta el estudio de la influencia del tiempo de reposo del extracto en solvente alcohólico (96%) de residuos provenientes de la producción vinícola, evaluándose la concentración de los compuestos fenólicos por alrededor de 114 días (un total de seis datos) y a su vez se sintetizaron nanopartículas de plata (NP Ag) por el método de química verde (biosíntesis) evaluándose también el potencial reductor del extracto respecto del precursor AgNO3 para la formación de NP Ag. La evaluación del extracto fue mediante la cuantificación del contenido de polifenoles por el método de FollinCiocalteu. Se realizó análisis por FTIR (Espectroscopía infrarroja por transformada de Fourier) únicamente a la muestra inicial para su evaluación comparativa entre extracto alcohólico de residuos vinícolas y NP Ag; las NP Ag fueron caracterizadas por espectrofotometría UV-Vis.(Ultravioleta-visible) Los resultados sugieren que a pesar de que el contenido de compuestos fenólicos se vea reducido en el tiempo, hay hipótesis que consideran un comportamiento constante y hasta incluso un incremento de la capacidad reductoras. Es así como los resultados por espectrofotometría de las NP Ag evidencian un incremento del pico de absorbancia que implica una mayor producción de nanoestructuras, siendo los antioxidantes los implicados en el proceso de reducción química.ABSTRACT In the agribusiness sector, the raw material is subjected to transformation processes to give it added value, for this purpose various methodologies are implemented which facilitate its consumption, but wine residues on the contrary generate one of the main environmental problems. This research adopts the study of the influence of the resting time of the extract in alcoholic solvent (96%) of residues from wine production, evaluating the concentration of phenolic compounds for about 114 days (a total of six data) and their once silver nanoparticles (NP Ag) were synthesized by the green chemistry method (biosynthesis), also evaluating the reducing potential of the extract with respect to the AgNO3 precursor for the formation of NP Ag. The evaluation of the extract was by quantifying the polyphenol content by the Follin-Ciocalteu method. FTIR (Fourier transform infrared spectroscopy) analysis was performed only to the initial sample for comparative evaluation between alcoholic extract of wine residues and NP Ag; NP Ag were characterized by UV-Vis spectrophotometry (Ultraviolet-visible). The results suggest that despite the fact that the content of phenolic compounds is reduced over time, there are hypotheses that consider a constant behavior and even an increase in reducing capacity. This is how the results by spectrophotometry of NP Ag show a increase in absorbance peak that implies a greater production of nanostructures, with antioxidants being the ones involved in the chemical reduction process