Analysis of XGaO3 (X = Ba and Cs) cubic based perovskite materials for photocatalytic water splitting applications: a DFT study.

Energy conversion has become an important technology for meeting energy production and consumption in the modern era. Water splitting and solar cell technologies are projected to close the gap between demand and consumption. Therefore, XGaO3 (X = Ba and Cs) compounds having characteristics i.e., electrical, optical, mechanical, and structural are depicted by using a density functional theory (DFT) based CASTEP software with ultrasoft pseudo-potential plane-wave and Generalized Gradient Approximation and Perdew Burke Ernzerhof exchange correlation functional (GGA-PBE). According to the findings, all of these compounds have a cubic "pm3m" structure with space group 221. The CsGaO3 and BaGaO3 have direct and indirect band gaps, with respect to electronic band-structure recreations. Density of states like total density of states (TDOS) and partial density of states (PDOS) commend the extent of localization of electrons in numerous bands. The optical properties of these compounds are explored by adjusting dispersion curve/relation for theoretical dielectric function (DF) scale to the corresponding peaks. As a result, these materials could be used to consume light in the visible zone via photo catalysis. CsGaO3 in combination with BaGaO3 can produce effective results, so these compounds have a remarkable potential application for sensing and water splitting.

Photocatalytic Degradation of Textile Dye on Blended Cellulose Acetate Membranes.

This work aimed to investigate the degradation performance of natural cellulose acetate (CA) membranes filled with ZnO nanostructures. Photocatalytic degradation of reactive toxic dye methylene blue (MB) was studied as a model reaction using UV light. A CA membrane was previously casted and fabricated through the phase inversion processes and laboratory-synthesized ZnO microparticles as filler. The prepared membrane was characterized for pore size, ultrafiltration (UF) performance, porosity, morphology using scanning electron micrographs (SEM), water contact angle and catalytic degradation of MB. The prepared membrane shows a significant amount of photocatalytic oxidation under UV. The photocatalytic results under UV-light radiation in CA filled with ZnO nanoparticles (CA/ZnO) demonstrated faster and more efficient MB degradation, resulting in more than 30% of initial concentration. The results also revealed how the CA/ZnO combination effectively improves the membrane's photocatalytic activity toward methylene blue (MB), showing that the degradation process of dye solutions to UV light is chemically and physically stable and cost-effective. This photocatalytic activity toward MB of the cellulose acetate membranes has the potential to make these membranes serious competitors for removing textile dye and other pollutants from aqueous solutions. Hence, polymer-ZnO composite membranes were considered a valuable and attractive topic in membrane technology.

Synthesis and Characterization of Blended Cellulose Acetate Membranes.

The casting and preparation of ultrafiltration ZnO modified cellulose acetate membrane (CA/ZnO) were investigated in this work. CA membranes were fabricated by phase inversion using dimethylformamide (DMF) as a solvent and ZnO as nanostructures materials. Ultrafiltration (UF) performance, mechanical stability, morphology, contact angle, and porosity were evaluated on both CA- and ZnO-modified CA samples. Scanning electron microscopy (SEM) was used to determine the morphology of the membranes, showing different pore sizes either on rough surfaces and cross-sections of the samples, an asymmetric structure and ultra-scale pores with an average pore radius 0.0261 to 0.045 µm. Contact angle measurements showed the highest hydrophobicity values for the samples with no ZnO addition, ranging between 48° and 82.7° on their airside. The permeability values decreased with the increasing CA concentration in the casting solution, as expected; however, ZnO-modified membranes produced lower flux than the pure CA ones. Nevertheless, ZnO modified CA membranes have higher surface pore size, pore density and porosity, and improved surface hydrophilicity compared with pure CA membranes. The results indicated that the incorporated nano-ZnO tends to limit the packing of the polymer chains onto the membrane structure while showing antifouling properties leading to better hydrophilicity and permeation with consistent UF applications.