Effect of graphene size on the photocatalytic activity of TiO2/poly(3-hexylthiophene)/graphene composite films

Synthesis and enhanced photocatalytic application of porous nanocomposites of (r)GO/TiO2 embedded HCP (hyper crosslinked polymer)

Nanocomposites (r)GO/TiO₂/hyper crosslinked polymer (HCP) were prepared using ultrasonic-assisted method, and identified by (SEM), (EDS), (TEM), and (XRD) techniques. This study was performed to examine the effect of various operating parameters on photocatalytic degradation of Rhodamine B (Rh.B) over (r)GO/TiO₂ embedded HCP followed by an optimization study using response surface methodology (RSM) based on Box-Behnken design (BBD). The photocatalytic activity of rGO/TiO₂/polycalix[4]resorcinarene ((r)GTP) was evaluated using the cationic dye Rhodamine B as a pollutant model under solar light (intensity = 850 W/m²) between 10 and 12 am, June, Ahvaz, Iran. Response Surface Methodology was adopted for the optimization of degradation parameters viz pH, dye concentration, and nanocomposites dosage and contact time. The optimum values for the maximum Rhodamine B (Rh B) degradation of rGO/TiO₂/polycalix (rGTP) and GTP were obtained, in which the degradation of rGTP was 100% and the degradation efficiency of GO/TiO₂/polycalix (GTP) was 70%. ANOVA analysis results demonstrated that irradiation time and nanocomposite mass were the most significant parameters. It was found that rGO/TiO₂/polycalix[4]resorcinarene (rGTP) nanocomposite displayed the best degradation yield for the dye. The results showed that the rGTP nanocomposite displayed good EIS and CV properties besides being eco-friendly and reusable. It could also show a high capacity for the elimination of the dye in the industrial wastewaters.

Chemical and organoleptic changes of curd cheese stored in new and reused active packaging systems made of Ag-graphene-TiO2-PLA

The study reports obtaining, characterization and evaluation of the preservation efficacy of nano-Ag-graphene-TiO₂-polylactic acid (PLA) film during the storage of the curd cheese. The reusability of the active package was also evaluated. The mechanical resistance of the film was improved by 30% following the composite addition. Water vapour permeability decreased by 11-27% when the composite was incorporated into PLA in a mass percentage ranged between 0.5 and 3%. The highest fat permeability was obtained for PLA3% at 4 °C. The oxygen permeability of PLA3% is 24.6% lower than that of neat-PLA. PLA0.5% and PLA3% presented the highest antibacterial activity. PLA3% achieved the lowest solubility in food simulants at 4 °C compared to PLA and reference. The best active packages for curd storage were PLA0.5% and PLA3%. They showed also the lowest depreciation from the first to the second use. Their active role is kept 100% and 85% respectively, during the second use.

Hybrid materials based on conjugated polymers and inorganic semiconductors as photocatalysts: from environmental to energy applications

Hybrid materials photocatalysts based on conjugated polymers and inorganic semiconductors provide a sustainable way to remove pollutants or store energy in the form of solar fuels by processes such as water splitting, CO₂ photoreduction and NH₃ production (artificial photosynthesis).