Competence of tunable Cu2AlSnS4 chalcogenides hydrophilicity toward high efficacy photodegradation of spiramycin antibiotic resistance-bacteria from wastewater under visible light irradiation

Nowadays, removal of pollutants from urban wastewater treatment plants (UWTPs) remains a big challenge. The macrolides antibiotics are particularly present in higher levels in unprocessed wastewater and are often partially reduced by conservative managements. The photocatalysis process was categorised amongst the miscellaneous progressive oxidation methods (AOPs) with high capacity for successful removal of pharmaceuticals from numerous aqueous matrices. In the present work and for the first time, chemical spray pyrolysis was used to synthesize Cu2Fe1-xAlxSnS4 (x = 0, 0.25, 0.50, 0.75 and 1) thin films. Sprayed films were investigated using many techniques such as: MAUD software (Material Analysis Using Diffraction), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX), spectrophotometer and Hall effect and drop shape analysis system (DSA). MAUD software revealed a polycrystalline nature for Cu2AlSnS4 (CATS) with slight shift of diffraction peaks depicted at 2 theta = 27.84 degrees, 47.03 degrees and 55.93 degrees, which identified respectively to (0 0 2), (1 1 0) and (1 1 2) plans. In addition, SEM images show that Cu2AlSnS4 grows with many rod-shaped structures that closely attached to each other. It is clearly seen that CATS thin film exhibited the highest extinction coefficient value (K-ext) than other CFATS films. Additionally, a special emphasis focused on surface wettability of CFATS films showing a hydrophilic character surface using spiramycin (SPY) macrolide antibiotic liquid. Its worth mentioning that the hydrophilic type has a distinguished helpful role on the photocatalytic process that may be associated with the active surface area and the high adsorption of liquid. Based on the relationships between photocatalysis and hydrophilicity, the behaviors of SnO2:F, CATS films and coupled CATS/SnO2:F photocatalysis were tested using 20 mg/L of spiramycin (SPY) macrolide antibiotic in aqueous solution. Spiramycin removal competence using SnO2:F, CATS films and coupled CATS/SnO2:F was increased after being reused 120 min. Consequently, the current work can open a new area for effectiveness of CATS/SnO2:F surface which recognized in order to manufacture a self-disinfecting and self-cleaning, removal of high antibiotics bacteria-resistance.

Automated summary

The removal of pollutants from urban wastewater treatment plants remains a challenge. The photocatalysis process has shown high efficiency in removing pharmaceuticals from aqueous matrices. In this study, Cu2Fe1-xAlxSnS4 thin films were synthesized using chemical spray pyrolysis and their properties were analyzed. The Cu2AlSnS4 film exhibited the highest extinction coefficient and hydrophilic surface. The effectiveness of CATS/SnO2:F surface for removing spiramycin was tested and showed improved removal efficiency.