A study of the effect of temperature on the dielectric breakdown and lifetime of polyethylene materials under applied DC voltages at the nanoscale

The reported simulation results could be considered as one of the firsts modeling of the effect of temperature on the electrical breakdown phenomenon in polyethylene nanoscale. The breakdown begins with an abrupt increase of the external current density without a subsequent saturation. Our results show that the increase of temperature at a constant applied DC voltage leads to a breakdown and to a decrease of the insulator's lifetime. These outcomes are strongly linked to the injection of free charges into the sample and to the temporal evolution of the conduction current

Electric Poling Effect on Piezocatalytic BaTiO3/Polymer Composites for Coatings

BaTiO3-polymer paint composites were fabricated to examine piezocatalysis activities. Dye degradation and antibacterial activities were recorded under ultrasonication. The effect of polarization was also examined for the catalysis process. There were significant enhancements in catalysis performance in the poled sample; 80–90% dye degradation was recorded (240 min) in poled samples of BaTiO3-polymer paint composites. The above observations indicate that these composites can be utilized as coatings for self-cleaning applications

Piezo-photocatalytic activity of Bi2VO5.5 for methylene blue dye degradation

This study comprises the combined effect of piezocatalytic and photocatalytic activity to obtain improved piezo-photocatalytic dye degradation efficiency in visible light. Single-phase Bi2VO5.5 powder was prepared through solid-state synthesis at 750 °C in 8 h. Time-dependent photocurrent responses were conducted to understand the phenomenon of charge carrier transport in visible light. Bi2VO5.5 powder sample demonstrated high photocatalytic efficiency and good reusability possessing a bandgap value of 2.13 eV. Bi2VO5.5 powder sample attained ∼70% and ∼58% degradation efficiency during photocatalysis and piezocatalysis respectively. The piezo-photocatalytic methylene blue dye attained ∼82% degradation efficiency in 240 min duration of visible light illumination. The scavenger test depicted holes (h+) as the principal active species in the piezo-photocatalytic dye degradation. There incurred no severe loss in photocatalytic efficiency even after 4 cycles which proclaims the reusability of the Bi2VO5.5 powder sample. A study on the kinetic rate constant with varying dye concentrations was conducted. With varied dye concentration of 5, 10, 15 mg/L, the kinetic rate constant obtained was 0.00528, 0.0030, and 0.00125 min−1, respectively. Germination index was found through a phytotoxicity test using vigna radiata seeds. Here visible light along with mechanical energy has been used to achieve higher MB dye degradation efficiency through piezo-photocatalysis

Electric Poling Effect on Piezocatalytic BaTiO₃/Polymer Composites for Coatings

BaTiO3-polymer paint composites were fabricated to examine piezocatalysis activities. Dye degradation and antibacterial activities were recorded under ultrasonication. The effect of polarization was also examined for the catalysis process. There were significant enhancements in catalysis performance in the poled sample; 80–90% dye degradation was recorded (240 min) in poled samples of BaTiO3-polymer paint composites. The above observations indicate that these composites can be utilized as coatings for self-cleaning applications

Improved photoluminescence and spectroscopic features of Sm3+-doped alkali borate glasses by embedding silver nanoparticles

Influence of Ag nanoparticles (NPs) on the improvement in photoluminescence and spectroscopic features of Sm3+-doped alkali borate glass synthesized by the melt quenching process was systematically studied and analyzed. The increasing particle size of Ag NPs with the increase of AgCl concentration (0.1 - 0.5 mol%) causes the surface plasmon resonance peak to shift to a higher wavelength (red-shift) side. Electron microscopic investigation confirmed the presence of silver NPs in the SmLAB-1 glass sample with a median size of 4.57 nm. A significant enhancement in emission was noticed for 0.1 mol% AgCl concentration. Such improved emission was attributed to the enhanced local electric field by metallic NPs in the vicinity of Sm3+ ions and efficient energy transfer between Sm3+ ions and silver NPs. The Judd-Ofelt parameter, Omega(2) decreased as the concentration of Ag NPs increases, indicating increased symmetry and ionicity between the trivalent samarium ions and their ligands. These prepared glass compositions could have applications in solid-state devices such as LEDs and display applications