Visible Light Degradation of Naproxen by Enhanced Photocatalytic Activity of NiO and NiS, Scavenger Study and Focus on Catalyst Support and Magnetization

Abstract

This research was aimed to prepare a magnetically photocatalyst enabling to degrade pharmaceutical wastewater and detoxification of pollutant such as naproxen, by visible light irradiation. The nano-sized NiS and NiO photocatalysts exhibit higher reactivity than their microsized counterparts, but separation of the used photocatalyst from the degradation solution is hard and imperfect. To remove this difficulty, magnetic polypyrrole core-shell (Fe O @PPY) was synthesized and employed as catalyst support. The magnetization property of the synthesized photocatalysts measured by VSM technique indicated that the photocatalysts were sufficiently magnetized to be readily separated from degradation solution by use of external magnetic field. The DRS study showed that the band gap of the photocatalysts shifted to lower energy after immobilization on the support materials leading to higher degradation efficiency. The optimal efficiency was obtained with the catalysts loaded with 50% of NiO and 50% of NiS. The augmenting effect of H O and the inhibition influence of some organic and inorganic compounds on the degradation process were studied. Regeneration of the used photocatalyst was performed by heat treatment, and the catalyst treated at 400°C retained most of its initial capacity. The degradation capacity was kinetically fast, and the equilibrium was attained within 30 min.

Photocatalytic activity of NiS, NiO and coupled NiS–NiO for degradation of pharmaceutical pollutant cephalexin under visible light

“…From the TEM images of Fe 3 O 4 @PPY given in the previously published work, it was concluded that the core-shell structure was formed successfully. 13 Table 3S. † The TG-DTG curves of Fe 3 O 4 @PPY-NiO-NiS taken from between 25-800 C showed two distinct weight loss steps (Fig.…”

“…The mixture was shaken for 15 h at room temperature and the product was collected magnetically, washed with deionized water and methanol and dried at 70 C for 6 hours. 13 Similar procedure was followed for preparation of Fe 3 O 4 @PPY-NiO-NiS nanophotocatalyst. Each photocatalyst contained equal amount (10-80%) of NiO and NiS.…”

Photosensitive Hybrid Nanostructured Materials: The Big Challenges for Sunlight Capture

“…Another important conductive polymer is represented by polypyrrole (PPy), mostly used to produce nanohybrid photocatalysts for photodegradation of organic pollutants, and the photocatalytic performances of PPy-based materials have been affected by the fabrication method and type of irradiated light [277]. Many examples of hybrid nanomaterials with photocatalytic properties have been recently reported, in which PPy has been combined with different semiconductor metal oxides, such as TiO 2 [290,291] , for pollutants degradation or hydrogen production, ZnO [292][293][294], and its derivatives doped with other metals, ZnWO 4 [295], Fe 2 O 3 [296], or Fe 3 O 4 [297][298][299].…”

Optimization of photocatalytic degradation of naproxen from aqueous solutions with UV/ZnO process: Response Surface Methodology (RSM)

“…At high pH levels, OH radicals become O2 •and O2H • , which have a lower degrading activity than OH • . Thus, the efficiency of NPX degradation is reduced at high pH levels (Torki,and Faghihian, 2018).…”