Rational design of CdS-enwrapped polypyrrole nanoparticles for wastewater treatment: removal of hazardous pollutants in aqueous solutions.

The modern world requires a chemical industry that can run at low production costs while producing high-quality products with minimal environmental impact. The development of environmentally friendly, cost-effective, and efficient wastewater treatment materials remains a major problem for the sustainable approach. We prepared nanoscale cadmium sulfide (CdS)-enwrapped polypyrrole (PPy) polymer composites for degradation of organic pollutants. The prepared CdS@PPy nanocomposites were characterized by powder X-ray diffraction, scanning electron microscope (SEM), field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet-visible (UV) absorption spectroscopy, indicating proper intercalation between CdS and PPy. Consequently, the catalytic efficiency of the synthesized hybrid nanocomposites was analyzed through the degradation of methylene blue (MB) and rhodamine B (Rh B) under visible light irradiation. The measured degradation efficiency of the dye solutions under the photolysis process is about 18% and 23% for MB and Rh B dye, respectively. Furthermore, the recycle test result concludes that the CdS@PPy composite exhibits 91% and 89% of MB and Rh B dye degradation efficiency even at the 4th cycle, respectively. The positive synergistic impact of CdS and PPy may be the result of effective photocatalytic degradation of MB and RhB.

A High-Performance Supercapacitor Based on Hierarchical Template-Free Ni/SnO2 Nanostructures via Hydrothermal Method.

Novel flake-like Ni1-xSnxO2 particles were successfully prepared by template-free hydrothermal synthesis. The prepared samples were investigated for their properties by different characterization techniques. Scanning micrographs showed that the obtained particles consisted of nanoflakes. The X-ray diffraction results of the Ni1-xSnxO2 revealed the formation of mixed-phase Ni/SnO2 having the typical tetragonal structure of SnO2, and the cubic structure of Ni in a nanocrystalline nature. The doping with Ni had a certain influence on the host's lattice structure of SnO2 at different doping concentrations. Confirmation of the functional groups and the elements in the nanomaterials was accomplished using FTIR and EDS analyses. The electrochemical performance analysis of the prepared nanomaterials were carried out with the help of the CV, GCD, and EIS techniques. The specific capacitance of the synthesized nanomaterials with different concentrations of Ni dopant in SnO2 was analyzed at different scanning rates. Interestingly, a 5% Ni-doped SnO2 nanocomposite exhibited a maximum specific capacitance of 841.85 F g-1 at 5 mV s-1 in a 6 M KOH electrolyte. Further, to boost the electrochemical performance, a redox additive electrolyte was utilized, which exhibited a maximum specific capacitance of 2130.33 at 5 mV s-1 and an excellent capacitance retention of 93.22% after 10,000 GCD cycles. These excellent electrochemical characteristics suggest that the Ni/SnO2 nanocomposite could be utilized as an electrode material for high-performance supercapacitors.

Hybrid Ni-Boron Nitride Nanotube Magnetic Semiconductor-A New Material for Spintronics.

Here, we report the presence of ferromagnetism in hybrid nickel-boron nitride nanotubes (BNNTs) with an ordered structure, synthesized by chemical vapor deposition using elemental boron, nickel oxide as the catalyst, and ammonia gas as the source for nitrogen. In previous studies, the nanotubes were synthesized with two metal oxide catalysts, whereas here, only a single catalyst was used. The nanotube's structure was determined by X-ray diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy. Purity of the nanotubes synthesized at 1150 °C was exceptional and this was determined by Raman spectroscopy. The average diameter of the nanotubes was 63 nm. Based on the magnetic studies carried out, it can be confirmed that the synthesized hybrid material is ferromagnetic at room temperature. Cyclic voltammetry was carried out to confirm the dielectric nature of the nanotubes. These materials could pave ways to nanoscale devices. The well-known thermal stability of BNNTs would play a vital role in preventing thermal failures in such small-scale devices where overheating is a major concern. The presence of semiconducting and magnetic properties in a single material could be confirmed, which might be highly significant in the field of spintronics.