Synthesis of Phosphotungstic acid/S-doped g-C3N4 Photocatalyst and Its Photocatalytic Degradation of Organic Pollutants in Aqueous Solutions

Abstract

The S-doped g-C3N4 (SCN) was prepared by thermal condensation method using thiourea as a precursor, and then the phosphotungstic acid (PTA)/SCN composite photocatalytic material was prepared by reflux adsorption method. The photocatalytic degradation experiments of Rhodamine B showed that SCN20 had the highest photocatalytic degradation rate (74 %), which was 1.9 times and 3.5 times higher than that of PTA (39 %) and SCN (21 %), respectively. The photocatalytic degradation rate of SCN20 was increased by 5 times compared to that of SCN, indicating that the photocatalytic degradation performance of the composite material was significantly improved. The photocatalytic degradation mechanism study revealed that O2- was the main active species in the photocatalytic degradation of Rhodamine B, and the addition of PTA helped the effective separation of electrons-hole and improved the photocatalytic degradation rate. Our PTA/SCN is proposed as an environmental safety tool due to several advantages, such as low cost, convenient preparation, and efficient photocatalytic degradation of Rhodamine B.

Performance of Iron-Doped Titanium Dioxide-Loaded Activated Carbon Composite Synthesized by Simplified Sol–Gel Method for Ciprofloxacin Degradation under Ultraviolet Light

“…From Figure 9, it can be observed that at the ciprofloxacin concentration of 1 mg/L, the degradation rate of CIP basically did not increase after reaching 87.02% in 5 min, indicating that the catalyst could not degrade CIP when the ciprofloxacin concentration in the solution was too low, because the low ciprofloxacin concentration is not helpful to the accumulation of CIP on the surface of the photocatalyst. It reduces the concentration of the reactants accumulated on the surface of the photocatalyst, leading to the ineffective utilization of the catalytic active sites on the surface of the photocatalyst, thus failing to achieve the ideal degradation effect [50]. The degradation rate of the ciprofloxacin concentration at 3 mg/L was the highest, after which the degradation rate of ciprofloxacin by photocatalysis decreased.…”

Degradation of metribuzin in the UV/chlorine process: kinetic model, degradation by-products and transformation pathways

“…Moreover, there were five main conversion pathways after the oxidation of methylthio to form sulfinyl (M15). 2,58,63 ① route C1: After deamination of sulfoxide (M15), the hydrogen on the imino group (-NH) and methyl on sulfinyl were replaced by hydroxyl to form products M16 and M17. ② route C2: After hydroxyl attacked M15 to form M18, the sulfinyl group on M18 was replaced by hydroxyl to form product M19, and then the triazine ring was oxidized to form M20 and M21.…”