Potential of TiO2 with Various Au Nanoparticles for Catalyzing Mesotrione Removal from Wastewaters under Sunlight

Abstract

Nowadays, great focus is given to the contamination of surface and groundwater because of the extensive usage of pesticides in agriculture. The improvements of commercial catalyst TiO2 activity using different Au nanoparticles were investigated for mesotrione photocatalytic degradation under simulated sunlight. The selected system was 2.43 × 10−3% Au–S–CH2–CH2–OH/TiO2 (0.5 g/L) that was studied by transmission electron microscopy and ultraviolet-visible (UV-Vis) spectroscopy. It was found that TiO2 particles size was ~20 nm and ~50 nm, respectively. The Au nanoparticles were below 10 nm and were well distributed within the framework of TiO2. For 2.43 × 10−3% Au–S–CH2–CH2–OH/TiO2 (0.5 g/L), band gap energy was 2.45 eV. In comparison to the pure TiO2, addition of Au nanoparticles generally enhanced photocatalytic removal of mesotrione. By examining the degree of mineralization, it was found that 2.43 × 10−3% Au–S–CH2–CH2–OH/TiO2 (0.5 g/L) system was the most efficient for the removal of the mesotrione and intermediates. The effect of tert-butanol, NaF and ethylenediaminetetraacetic acid disodium salt on the transformation rate suggested that the relative contribution of various reactive species changed in following order: h+ > ●OHads > ●OHbulk. Finally, several intermediates that were formed during the photocatalytic treatment of mesotrione were identified.

Chemometric evaluation of different parameters for removal of tembotrione (agricultural herbicide) from water by adsorption and photocatalytic degradation using sustainable nanotechnology

“…From the results shown in Figure 2, it can be seen that the final degradation efficiency has almost no obvious change under simulated sunlight for 30 min when adding 3.0 mM tert ‐butanol, which proves that the ● OH free does not participate in the photodegradation of tembotrione. This can be explained by the fact that tert ‐butanol has the low affinity for TiO 2 surface which agrees with our previous results (Šojić Merkulov et al, 2020). In addition, this phenomenon can be consequence of acidic conditions (e.g., pH of suspension ~4.50), where besides ● OH, other active species (as and photogenerated h + ) also take parts in photocatalytic degradation of tembotrione.…”

Ecofriendly Green Synthesis of the ZnO-Doped CuO@Alg Bionanocomposite for Efficient Oxidative Degradation of p-Nitrophenol

“…For this purpose, experiments were performed by taking a 20 mL aliquot of 50 mg L –1 PNP at pH 1.98 with 11.59 mg of the ZnO/CuO@Alg BNC under 137 min of visible light irradiation. The individual aliquot sample was mixed with a 3 mM solution of different scavengers such as t -butyl alcohol (TBA, for the • OH radical), EDTA (for e – ), triphenyl phosphene (TPP, for the • O 2 – radical), and acrylamide (AA, for the h VB + scavenger). − The results are given in Figure , which suggests that the rate of photodegradation was affected to a high extent with an antagonistic trend from 98.12 to 54.16% in the presence of TBA. Because TBA is known as a scavenger for trapping of bulk • OH radicals from the reaction medium, a decreased photocatalytic efficiency has been received.…”

“…Furthermore, there is a generation of ( • OH) radicals by the attack of trapped electrons on ( • HO 2 ) radicals, which is accountable for the effective photocatalytic degradation of PNP through eqs –. It may be inferred that during the mineralization process of PNP, the attack of ( • OH) resulted in ring opening of the PNP resulting in aliphatic compounds, which further converts into CO 2 , H 2 O, and other inorganic compounds . The proposed mechanism is schematically shown in Figure .…”

“…It may be inferred that during the mineralization process of PNP, the attack of ( • OH) resulted in ring opening of the PNP resulting in aliphatic compounds, which further converts into CO 2 , H 2 O, and other inorganic compounds. 57 The proposed mechanism is schematically shown in Figure 9. In support of the mechanism proposed in Figure 9, total organic carbon (TOC) and chemical oxygen demand (COD) studies were performed, which are given in Figure S5a,b.…”

Sonochemical construction of hierarchical strontium doped lanthanum trisulfide electrocatalyst: An efficient electrode for highly sensitive detection of ecological pollutant in food and water

“…Several analytical methods have been credited for the determination of MTO. The methods available for the detection of mesotrione are high-performance liquid chromatography (HPLC), gas-chromatography (GC), liquid chormatography-mass spectroscopy (LC-MS), colorimetric and diode array detectors [15] , [16] , [17] , [18] , [19] , [20] , [21] . These methods are sensitive but involve the use of hazardous reagents/solvents; time-consuming some may not be selective in detection.…”