Morphology Control of TiO Nanorods Using KBr Salt for Enhancing the Photocatalytic Activity of TiO and MoS/TiO Heterostructures.

In this study, the effect of KBr salt on the growth of TiO nanorods (NRs) was systematically studied. The addition of KBr with different concentrations provides a controllable growth of TiO NRs using hydrothermal method. The results revealed that the presence of KBr molecules affects the growth rate by suppressing the growth in the lateral direction and allowing for axial growth. This results in affecting the morphology by decreasing the diameter of the nanorods, and increasing the free space between them. Enhancing the free spaces between the adjacent nanorods gives rise to remarkable increase in the internal surface area, with more exposure side surface. To obtain benefit from the enlargement in the inner surface area, TiO NRs were used for the preparation of MoS/TiO heterostructures. To study the influence of the morphology on their activity, TiO NRs samples with different KBr concentrations as well as the MoS/TiO heterostructures were evaluated towards the photocatalytic degradation of Rhodamine B dyes.Open Access funding provided by Qatar National Library

Review on the visible light photocatalysis for the decomposition of ciprofloxacin, norfloxacin, tetracyclines, and sulfonamides antibiotics in wastewater

Antibiotics are chemical compounds that are used to kill or prevent bacterial growth. They are used in different fields, such as the medical field, agriculture, and veterinary. Antibiotics end up in wastewater, which causes the threat of developing antibacterial resistance; therefore, antibiotics must be eliminated from wastewater. Different conventional elimination methods are limited due to their high cost and effort, or incomplete elimination. Semiconductor-assisted photocatalysis arises as an effective elimination method for different organic wastes including antibiotics. A variety of semiconducting materials were tested to eliminate antibiotics from wastewater; nevertheless, research is still ongoing due to some limitations. This review summarizes the recent studies regarding semiconducting material modifications for antibiotic degradation using visible light irradiation.Scopu

Synthesis and Optimization of a Highly Stable and Efficient BN/TiO2 Nanocomposite for Phenol Degradation: A Photocatalytic, Mechanistic and Environmental Impact Study

Different BN/TiO2 nanocomposites were prepared hydrothermally, and their ratio was optimized to get the best photocatalytic performance towards phenol degradation. They were characterized by x-ray photoelectron spectroscopy, x-ray diffraction, Fourier transform infrared spectroscopy, thermal gravimetric analysis, scanning and transmission electron microscopies coupled with energy dispersive x-ray units, BET surface area, and UV-Vis diffuse reflectance. The bandgap energy was reduced from 3.35 to 2.95 eV due to the formation of the B-O-Ti bond. This allowed the exploitation of the visible light and inhibited the TiO2 e(-)/h(+) recombination, and consequently, the photocatalytic activity of TiO2 was dramatically improved. Almost 90 % mineralization of 20 ppm phenol solution was achieved within 30 min under simulated sunlight. The as-prepared composite showed excellent stability and reusability. Mechanistic analysis indicated that O2.- and h(+) played a crucial role in phenol degradation. The nanocomposite ' s biocompatibility and environmental impact were evaluated by analyzing its potential toxicity in vivo using the zebrafish embryos. 96-hpf acute toxicity assays, including the mortality rate assay (to obtain the LC50 values) and teratogenic assays (to obtain the No Observed Effect Concentration, NOEC) was conducted. The LC50 value for BN/TiO2 was 482.5 mg L-1, and the NOEC was 100 mg L-1. Based on LC50 value and according to the Fish and Wildlife Service (FWS) acute toxicity rating scale, the photocatalyst is "practically not toxic.