Dandan Wang

Specific oriented recognition of a new stable ICTX@Mfa with retrievability for selective photocatalytic degrading of ciprofloxacin

A new imprinted photocatalyst ICTX@Mfa is prepared by employing a molecular imprinting technique, which is authenticated via a variety of modern analysis methods. It exhibits superior specific oriented recognition capability, stability and retrievability for selectively degrading common antibiotic ciprofloxacin molecules under visible light. Through gaining an insight into the photocatalytic mechanism of ciprofloxacin molecules over ICTX@Mfa, we can confirm that the generation of holes and hydroxyl radicals plays a major role in degrading ciprofloxacin in virtue of the active species detection experiments. This work puts forward a new design idea and provides an illustrative example for selective oriented removal of the specified organic pollutant molecules according to practical requirements.

Surface imprinting of a g-C3N4 photocatalyst for enhanced photocatalytic activity and selectivity towards photodegradation of 2-mercaptobenzothiazole

In the present work, based on Fe3O4/g-C3N4 as the support, 2-mercaptobenzothiazole (MBT) as the template molecule, and pyrrole as the functional monomer, we synthesized magnetic conductive imprinted photocatalysts (MCIPs) that were significantly efficient and stable through a suspension polymerization method. Moreover, the MCIPs not only exhibited a higher photodegradation capacity for MBT under visible light irradiation, but also possessed good selectivity. The specific surface areas of the resultant MCIPs were approximately four times that of pure g-C3N4. Furthermore, the results indicated that h+ was the major reactive species in the photocatalytic reaction system. The photodegradation mechanism was also discussed by analyzing the mass spectrum (MS), and the results demonstrated that MBT was degraded to H2O, CO2 and other small molecules, step by step. In addition, after five cycles, the MCIPs still showed high photocatalytic efficiency, indicating that the as-prepared MCIPs had excellent photochemical stability and good prospects for application in water treatment.

Selective photodegradation of 2-mercaptobenzothiazole by a novel imprinted CoFe2O4/MWCNTs photocatalyst

A novel imprinted CoFe2O4/MWCNTs photocatalyst was prepared through the combination of a hydrothermal method and suspension polymerization based on 2-mercaptobenzothiazole (MBT) as the molecular template, pyrrole as the imprinted functional monomer and conductive polymerizable monomer, and CoFe2O4/MWCNTs as the matrix material. The results indicated that the surface imprinted layer was successfully coated on the surface of CoFe2O4/MWCNTs and polypyrrole (PPy) was formed and existed in the surface imprinted layer, the magnetic saturation value of the novel imprinted CoFe2O4/MWCNTs photocatalyst was 19 emu g−1. Moreover, compared with other photocatalysts, the novel imprinted CoFe2O4/MWCNTs photocatalyst not only had a high photocatalytic efficiency (57.09%), but also possessed a strong ability for selective recognition and photodegradation of MBT (the coefficients of selectivity of the novel imprinted CoFe2O4/MWCNTs photocatalyst relative to CoFe2O4/MWCNTs and the non-imprinted CoFe2O4/MWCNTs photocatalyst was 3.37 and 3.28, respectively). In addition, in the process of the photodegradation reaction, h+ and ˙OH were the main oxidative species, ˙O2− played a very small role.

Enhanced selective photocatalytic properties of a novel magnetic retrievable imprinted ZnFe2O4/PPy composite with specific recognition ability

A novel magnetic retrievable imprinted photocatalyst with the antigen/antibody-like function was obtained by coupling the imprinted polymer onto ZnFe2O4 nanocrystals. The morphology, structure and properties of the imprinted ZnFe2O4/PPy composite were characterized and revealed that a tight junction was formed between ZnFe2O4 and the imprinted polymer layer. Compared with non-imprinted ZnFe2O4/PPy composite, imprinted ZnFe2O4/PPy composite not only had high photocatalytic efficiency, but also possessed the strong selective ability to specifically recognize and preferentially degrade ciprofloxacin. It was worth noting that the selectivity of the imprinted ZnFe2O4/PPy composite eliminated the interference of the spatial structure of different pollutants and truly realized the function of specific recognition. This work provided a new idea for preparing an imprinted photocatalyst and realized specific recognition.