Photocatalysis coupled with adsorption of AC@Ni0.5Cu0.5Fe2O4 in peroxydisulfate assisted system efficiently enhance ciprofloxacin removal

Microstructure and phase evolution in increasing the amount of mo and Ti of non-equiatomic CoFeNi-based medium entropy alloys for organic wastewater treatment

The effect of the combined addition of Mo and Ti on the phase evolution of non-equiatomic (CoFeNi)100-2.5xMoxTi1.5x (x = 2,4,6,8,10,12) alloys produced by high-energy ball-milling was investigated. Based on the preliminary phase stability criteria, solid solution formation is expected for each composition, a face-centred structure (FCC) phase if x is less than 10, and FCC and body-centred structure (BCC) phase in other cases. After 35 h of milling, solid solution structures were successfully produced in all samples; an FCC, two BCC structure phases, and a small amount of Co phase were identified based on X-ray diffraction. One of the BCC phases is Mo-based (BCC1(Mo)), while the other is a Fe-based (BCC2(Fe) solid solution. Increasing the combined amount of Mo and Ti alloying up to 20 at% (x = 8), the amount of the FCC structure was dominant, while above 20 at% (x = 10), the amount of the two BCC lattice structures was predominant. The average particle sizes were smaller than 3 μm. The specific surface area of all composition powders was less than 0.25 m2/g, which is extremely rare for a catalyst. All HEA powders containing Mo and Ti demonstrated enhanced photocatalytic activity in the decolorisation of Rhodamine B dye (RhB). The optimum conditions for RhB decolorisation were a pH of 2 and a catalyst dosage of 1 g/L. Under these conditions, (CoFeNi)85Mo6Ti9, (CoFeNi)80Mo8Ti12, and (CoFeNi)70Mo12Ti18 demonstrated high efficiencies of 97.6, 98.6 and 98.7%, respectively, already in the first minute of reaction.

Multiaperture g-C3N4@SiO2 to activate peroxydisulfate via visible light for efficient Rhodamine B removal

The sulfate radical-based advanced oxidation process (SR-AOPs) has been verified as a promising method to handle the persistent organic compounds in water using peroxydisulfate (PDS) as oxidant. A Fenton-like process was constructed and showed great potential to remove organic pollutants using visible-light-assisted PDS activation. The g-C₃N₄@SiO₂ was synthesized via thermo-polymerization, and characterized using powder X-ray diffraction (XRD), scanning electron microscope equipped with an energy-dispersive X-ray (SEM-EDX), X-ray photoelectron spectroscopy (XPS), N₂ adsorption-desorption, Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) method, photoluminescence (PL), transient photocurrent, and electrochemical impedance. Photocatalytic performance was demonstrated using the removal rate of Rhodamine B (RhB), and 96.08% RhB was removed from the solution within 50 min (10 mg/L in 200 mL, g-C₃N₄@SiO₂ = 0.25 g/L, pH = 6.3, PDS = 1 mmol/L). The free radical capture experiment proved that HO^•, h⁺, [Formula: see text] and [Formula: see text] were generated and removed RhB. The cyclic stability of g-C₃N₄@SiO₂ has also been studied, and the result shows no noticeable difference in the six cycles. The system of visible-light-assisted PDS activation might provide a novel strategy for wastewater treatment and must be an environment-friendly catalyst.