A novel BiVO4-GO-TiO2-PANI composite for upgraded photocatalytic performance under visible light and its non-toxicity

Polypyrrole-Bonded Quaternary Semiconductor LiCuMo2O11-Graphene Nanocomposite for a Narrow Band Gap Energy Effect and Its Gas-Sensing Performance

In this study, we demonstrate the fabrication and characterization of a new quaternary semiconductor nanocomposite of LiCuMo2O11/graphene oxide/polypyrrole (LCMGP) via a hydrothermal method and testing of an NH3 and H2SO4 sensor operating in gaseous states at room temperature. We used X-ray diffraction, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy to characterize the properties of LCMGP nanostructures. Our sensor is capable of detecting NH3 and H2SO4 and quantifying their concentration in the gas flow. These results have been confirmed by exposing the sensor to different concentrations of NH3 and H2SO4 (100-1000 ppm). The obtained results confirm the exceptional sensing properties of the graphene-polymer-combined quaternary semiconductor nanocomposite related to the oxidation-reduction process that can be used for detection, identification, and quantification purposes.

Phytosynthesis of BiVO4 nanorods using Hyphaene thebaica for diverse biomedical applications

Biosynthesis of bismuth vanadate (BiVO₄) nanorods was performed using dried fruit extracts of Hyphaene thebaica as a cost effective reducing and stabilizing agent. XRD, DRS, FTIR, zeta potential, Raman, HR-SEM, HR-TEM, EDS and SAED were used to study the main physical properties while the biological properties were established by performing diverse assays. The zeta potential is reported as − 5.21 mV. FTIR indicated Bi–O and V–O vibrations at 640 cm⁻¹ and 700 cm⁻¹/1120 cm⁻¹. Characteristic Raman modes were observed at 166 cm⁻¹, 325 cm⁻¹ and 787 cm⁻¹. High resolution scanning and transmission electron micrographs revealed a rod like morphology of the BiVO₄. Bacillus subtilis, Klebsiella pneumonia, Fusarium solani indicated highest susceptibility to the different doses of BiVO₄ nanorods. Significant protein kinase inhibition is reported for BiVO₄ nanorods which suggests their potential anticancer properties. The nanorods revealed good DPPH free radical scavenging potential (48%) at 400 µg/mL while total antioxidant capacity of 59.8 µg AAE/mg was revealed at 400 µg/mL. No antiviral activity is reported on sabin like polio virus. Overall excellent biological properties are reported. We have shown that green synthesis can replace well established processes for synthesizing BiVO₄ nanorods.

Polymer Nanocomposites for Photocatalytic Applications

In the present comprehensive review we have specifically focused on polymer nanocomposites used as photocatalytic materials in fine organic reactions or in organic pollutants degradation. The selection of the polymer substrates for the immobilization of the active catalyst particles is motivated by several advantages displayed by them, such as: Environmental stability, chemical inertness and resistance to ultraviolet radiations, mechanical stability, low prices and ease availability. Additionally, the use of polymer nanocomposites as photocatalysts offers the possibility of a facile separation and reuse of the materials, eliminating thus the post-treatment separation processes and implicitly reducing the costs of the procedure. This review covers the polymer-based photocatalytic materials containing the most popular inorganic nanoparticles with good catalytic performance under UV or visible light, namely TiO2, ZnO, CeO2, or plasmonic (Ag, Au, Pt, Pd) NPs. The study is mainly targeted on the preparation, photocatalytic activity, strategies directed toward the increase of photocatalytic efficiency under visible light and reuse of the hybrid polymer catalysts.