In this work, well-designed zinc oxide-reduced graphene oxide (ZnO-rGO) nanorods (NRs) were synthesized by a hydrothermal method using electrospun ZnO-rGO seed layers. The ZnO-rGO seed layers were fabricated on fluorine-doped tin oxide (FTO) glass substrates through calcined of electrospun nanofibers at 400 °C in the air for 1 h. The nanofibers were prepared by electrospinning different spinning voltages and a spinning solution containing zinc acetate, polyvinyl pyrrolidone, and 0.2 wt% rGO. From a detailed characterization using various analytical techniques, for instance, X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), Raman spectroscopy, photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS), the dependence of the structure, morphology, and optical properties of the ZnO-rGO NRs was demonstrated. The photocatalytic activities of ZnO-rGO nanorods...

Water, essential for all life, faces contamination challenges due to industrialization and unchecked urban development, producing pollutants such as organic dyes, detergents, heavy metals, and pesticides. This has emerged as one of the most pressing environmental concerns in recent years, with a particular emphasis on organic dyes due to their demonstrated health-related concerns. In this context, this paper reviews the use of photocatalysis as a wastewater treatment method, highlighting its significant potential for removing organic dyes from aqueous solutions. Additionally, the focus is on the design, development, performance enhancement, and overall research progress in fabricating graphene-based semiconductor nanocomposites as photocatalysts. Representative examples are discussed, emphasizing the potential of these nanocomposites in degrading toxic organic dyes through photocatalysis...

Introduction: as a consequence of the social isolation associated with COVID-19, depression and anxiety are two of the most frequent affective disorders in the elderly. Objective: To determine the relationship between depression and anxiety with social isolation in older adults in a first level care clinic. Material and methods: An observational descriptive cross-sectional study was carried out in patients 65 years and older, of both sexes, in social isolation due to confinement. A validated questionnaire was applied for the diagnosis of anxiety and depression, as well as another with questions about social isolation and sociodemographic variables. The Mann-Whitney and Kruskall Wallis U statistical tests were used, with a significance level of 0.05. SPSS program. Version 26. Results: 286 older adults were included, with an average age of 70.6 years, 54.2 % belonged to the female sex. Reg...

Capacitive deionization (CDI) is an emerging water desalination technology whose principle lies in ion electrosorption at the surface of a pair of electrically charged electrodes. The aim of this study was to obtain the best performance of a CDI cell made of activated carbon as the active material for water desalination. In this work, electrodes of different active layer thicknesses were fabricated from a slurry of activated carbon deposited on graphite sheets. The as-prepared electrodes were characterized by cyclic voltammetry, and their physical properties were also studied using SEM and DRX. A CDI cell was fabricated with nine pairs of electrodes with the highest specific capacitance. The effect of the flow rate on the electrochemical performance of the CDI cell operating in charge–discharge electrochemical cycling was analyzed. We obtained a specific absorption capacity (SAC) of 10...

Capacitive deionization (CDI) is a promising and cost-effective technology that is currently being widely explored for removing dissolved ions from saline water. This research developed materials based on activated carbon (AC) materials modified with zinc oxide (ZnO) nanorods and used them as high-performance CDI electrodes for water desalination. The as-prepared electrodes were characterized by cyclic voltammetry, and their physical properties were studied through SEM and XRD. ZnO-coated AC electrodes revealed a better specific absorption capacity (SAC) and an average salt adsorption rate (ASAR) compared to pristine AC, specifically with values of 123.66 mg/g and 5.06 mg/g/min, respectively. The desalination process was conducted using a 0.4 M sodium chloride (NaCl) solution with flow rates from 45 mL/min to 105 mL/min under an applied potential of 1.2 V. Furthermore, the energy efficie...

Capacitive deionization (CDI) is a promising and cost-effective technology that is currently being widely explored for removing dissolved ions from saline water. This research developed materials based on activated carbon (AC) materials modified with zinc oxide (ZnO) nanorods and used them as high-performance CDI electrodes for water desalination. The as-prepared electrodes were characterized by cyclic voltammetry, and their physical properties were studied through SEM and XRD. ZnO-coated AC electrodes revealed a better specific absorption capacity (SAC) and an average salt adsorption rate (ASAR) compared to pristine AC, specifically with values of 123.66 mg/g and 5.06 mg/g/min, respectively. The desalination process was conducted using a 0.4 M sodium chloride (NaCl) solution with flow rates from 45 mL/min to 105 mL/min under an applied potential of 1.2 V. Furthermore, the energy efficie...

In the present work, a TiO2/zeolite photocatalyst was synthesized by dispersing TiO2 nanoparticles obtained through the sol-gel method onto the surface of natural zeolite derived from ignimbrite residue. The zeolite was obtained from an ignimbrite rubble treatment collected from a quarry in Arequipa City, Peru. The research focused on the effect of zeolite on the TiO2 nanoparticles. The synthesized photocatalysts were characterized using various techniques, including field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray (EDS), X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS), and Brunauer–Emmett–Teller surface area analysis (BET). The results revealed that the TiO2/zeolite samples displayed high crystallinity, with TiO2 being present in three phases and zeolite being present in the analcime phase. Furthermore, these samples exhibited a band gap ...

TiO2 nanotubes were synthesized by alkaline hydrothermal treatment of TiO2 nanoparticles with a controlled proportion of anatase and rutile. Tailoring of TiO2 phases was achieved by adjusting the pH and type of acid used in the hydrolysis of titanium isopropoxide (first step in the sol-gel synthesis). The anatase proportion in the precursor nanoparticles was in the 3–100% range. Tube-like nanostructures were obtained with an anatase percentage of 18 or higher while flake-like shapes were obtained when rutile was dominant in the seed. After annealing at 400°C for 2 h, a fraction of nanotubes was conserved in all the samples but, depending on the anatase/rutile ratio in the starting material, spherical and rod-shaped structures were also observed. The photocatalytic activity of 1D nanostructures was evaluated by measuring the deactivation of E. coli in stirred water in the dark and un...

ZnO nanorods (NRs) films, nitrogen-doped (ZnO:N), and ZnO doped with nitrogen and decorated with silver nanostructures (ZnO:N-Ag) NRs films were vertically supported on undoped and N doped ZnO seed layers by a wet chemical method. The obtained films were characterized structurally by X-ray diffraction. Morphological and elemental analysis was performed by scanning electron microscopy, including an energy dispersive X-ray spectroscopy facility and their optical properties by Ultraviolet-Visible Spectroscopy. Analysis performed in the NRs films showed that the nitrogen content in the seed layer strongly affected their structure and morphology. The mean diameter of ZnO NRs ranged from 70 to 190 nm. As the nitrogen content in the seed layer increased, the mean diameter of ZnO:N NRs increased from 132 to 250 nm and the diameter dispersion decreased. This diameter increase occurs simultaneousl...

A novel methodology was employed to prepare new nanocomposites with photocatalytic properties based on Ce-doped TiO2 nanoparticles arranged over a layered silicate. The catalysts were porous materials formed by exfoliated silicate layers surrounded by anatase nanoparticles. In this way, the anatase was doped by different amounts of Ce, yielding to catalysts with light absorption properties on the visible region. The photocatalytic behavior was tested for different reactions: adsorption and photocatalysis, showing outstanding and promising results for the removal of bacteria by using solar light as an energy source. The influence of the physicochemical properties of the catalyst and the reaction parameters will be studied in detail to manage new catalysts for the disinfection of drinking water.