Retracted: Self‐floating Cu/N co‐doped TiO₂/diatomite granule composite with enhanced visible‐light‐responsive photoactivity and reusability

Abstract

BACKGROUND The remnants of antibiotics in aquatic environments have emerged as hazardous pollutants. To eliminate these remnants, new methods have been proposed, including photocatalysis. Powdery photocatalysis has been widely studied, yet its several disadvantages such as light‐harvesting and recyclability in suspension systems have remained as bottlenecks for practical applications. A recent report on a floating photocatalyst provided an alternative method to solve the above problems. In the present paper, TiO2 nanoparticles were co‐doped by copper (Cu) and nitrogen (N), and then immobilized onto substrate diatomite. The composite powder was granulated to produce a self‐floating granule catalyst (Cu/N co‐doped TiO2/diatomite hybrid granules), denoted as CN‐TDHG. The photoactivity of CN‐TDHG was investigated via the degradation of antibiotic oxytetracycline (OTC) under visible light. RESULTS The characterization results indicated that Cu/N co‐doped TiO2 nanoparticles were successfully dispersed onto the surface of diatomite. Compared to powdery composite, the granule catalyst presented enhanced photodegradation efficiency. Optimal values of both doping amount and granule dosage were determined. The optimal granule catalyst removed 92.5% OTC within 150 min reaction time. Based on the experimental results, the corresponding photodegradation mechanism was proposed. CONCLUSION The self‐floating granule catalyst presented enhanced photodegradation capability, thanks to the synergy between Cu‐ and N‐dopants, as well as the adsorption and degradation dual processes between TiO2 and diatomite. Moreover, CN‐TDHG could simply be filtered from the surface of the water matrix, and presented good stability and reusability after five repetitions, proving itself as a promising candidate for the remediation of water environment. © 2018 Society of Chemical Industry

Retracted: The fabrication of magnetic recyclable nitrogen‐doped titanium dioxide/calcium ferrite/diatomite heterojunction nanocomposite for improved visible‐light‐driven degradation of tetracycline

“…As shown in Fig. (a), all of their BET isotherms are recognized as type IV based on BDDT classification . The shape of hysteresis loops from 0.5 to 0.9 of relative pressure is identified as H3 according to IUPAC classification, and could be assigned to the slit‐shaped pores, whose sizes are not well‐proportioned .…”

Retracted: Visible‐light‐driven mitigation of antibiotic oxytetracycline and disinfection of Escherichia coli using magnetic recyclable Ag‐modified zinc ferrite/diatomite ternary hybrid material

“…However, UV light comprises only 4% of the solar light spectrum and thus has inhibited practical applications . Thus, the development of visible‐light‐active photocatalysts is increasingly required for the elimination of OTC in aquatic environments …”

Heterogeneous Photo‐Fenton Catalytic Oxidation of Ciprofloxacin Using LaFeO3/Diatomite Composite Photocatalysts under Visible Light

“…[21] The strong adsorption capacity of diatomite attracted more target pollutants, enriched them around the photocatalytic reaction sites, provided a larger contact area, and thus improved the decomposition efficiency. [22] Ren's study showed that the chemical binding of Bi 2 O 3 and diatomite improved the formation and thermal stability of phase like, displaying better visible light catalytic activity than Bi 2 O 3 . [23] As far as we know, there are few reports on the photocatalytic oxidation of CIP with LaFeO 3 /Diatomite composite.…”