Graphene quantum dots based on maltose as a high yield photocatalyst for efficient photodegradation of imipramine in wastewater samples

چکیده مقاله

Purpose

In this work, for the first time, graphene quantum dots (GQDs) based on maltose were fabricated as a new photocatalytic material to the photodegradation of imipramine (as a persistence organic pollutant) under light irradiation.

Methods

The synthesized GQDs were characterized by different instrumentation approaches such as X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), nitrogen adsorption/desorption, and transmission electron microscopy (TEM). A Box–Behnken design (BBD) and the response surface methodology (RSM) were applied for the optimization of different factors that affect the overall photocatalytic yield.

Results

Under the optimized conditions (pH of the sample solution: 2.0; photocatalyst dosage: 0.1 mg mL⁻¹; UV exposure time: 80 min), the highest achievable reduction efficiency was obtained about 80%. The stability and reusability of the synthesized photocatalytic material were investigated in four reaction cycles (80 min), which showed only a 15% photo-activity loss after the fourth photocatalytic runs.

Conclusions

The proposed method was successfully applied to degrade the mentioned drug in the real wastewater samples by about 70%. Regarding the mentioned advantages by the proposed method, this new kind of photocatalytic material possesses a strong potential for photodegradation of pollutants in industrial wastewater samples.