Effect of Si doping on the photocatalytic activity and photoelectrochemical property of TiO2 nanoparticles

Multifunctional leather finishing vs. applications, through the addition of well-dispersed flower-like nanoparticles

In the present paper, multifunctional flower-like nanoparticles were synthesized to be used in the leather finishing. They are capable of conferring simultaneously and synergistic antimicrobial, self-cleaning, light resistance, hydrophobic, mechanical, thermal, and fluorescent properties due to the presence of Ag, TiO2, and SiO2 NPs. These nanoparticles form a "flower-like" structure in which the "pistil" is made up of TiO2 and the "petals" that surround it of silver nanoparticles and silica nanoparticles, whose dimensions are of the order of ten nanometers. Their surfaces enjoy abundant hydrophilic functionalities to be dispersed within inks commonly used during the leather finishing process. Leathers functionalized with these nanomaterials showed significantly improved self-cleaning properties after 15 h of exposure to UV light, and antibacterial properties 10 times higher than that shown by the untreated samples. Aging tests were performed (ISO 105-B02, ISO 17228, SAEJ 2412). ΔE, color variation decreased by approximately 30%, if compared with samples not refined with flower-like NPs. Furthermore, the results of the mechanical tests (ISO 17076, FCA 50444) evidence amazing properties, e.g. abrasion resistance more than significantly improved, increase in resistance from 1500 cycles for the untreated samples to 3000 cycles for the leathers finished with flower-like NPs. The contact angle analysis, capturing the angle that traces the air-water to water-substrate interface from the origin of the air-water-substrate contact point at the edge, is practically unchanged after 10 s in the case of nanoparticles containing finishing.

High-throughput HSE study on the doping effect in anatase TiO2

Systematic study on the doping effects of anatase TiO₂ doped with 40 kinds of elements by high-throughput HSE06 calculations.

Photocatalytic activity of TiO₂ nanoparticles synthesized in presence of ammonium hexafluorosilicate

A series of silicon incorporated TiO2 with anatase crystalline phase were prepared via sol-gel using ammonium hexafluorosilicate (AHFS). The synthesized products were characterized using X-ray diffraction, FTIR, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV-vis diffuse reflectance spectrophotometry (DRS), energy dispersive X-ray analysis (EDX) and BET surface area measurement. Presence of Si-O-Ti bonds is revealed based on the XPS results. The products were tested for their activity as photocatalysts for degradation of congo red as a prob molecule. The 20% AHFS incorporation displayed the highest photocatalytic activity. This adequate amount of AHFS was beneficial for transferring photogenerated electron and reducing the recombination of electron-holes.