Enhanced photocatalytic activity of two dimensional ternary nanocomposites of ZnO-Bi2WO6-Ti3C2 MXene under natural sunlight irradiation

The design and development of advanced photocatalysts for water purification have attracted much attention from researchers in recent years. In this context, the two-dimensional (2D) semiconducting materials have shown excellent photocatalytic properties due to their merits of high surface area, confined longitudinal dimensions and excellent capability of efficient separation and transfer of photogenerated charge carriers. Herein, we report a novel 2D-2D-2D ternary photocatalyst ZnO-Bi2WO6-Ti3C2 by using a two-step electrostatic assembly route. The formation of the individual materials and nanocomposites was confirmed by x-ray diffraction and 2D morphology was ascertained by electron microscopy studies. The as-prepared photocatalysts were utilized for the degradation of a colorless pharmaceutical pollutant, ciprofloxacin (CFX) under natural sunlight irradiation. It was found that the optimized ternary photocatalyst showed a maximum degradation (similar to 77%) of CFX in 160 min. The mechanistic investigation showed that upon nanocomposite formation, the electrons flow from ZnO and Bi2WO6 to Ti3C2, implying that MXene plays an important role in the separation of photogenerated charges and thereby enhancing the photocatalytic activity. This work paves the way for the design and development of efficient photocatalysts for environmental remediation.

Automated summary

The study presents a novel 2D ternary photocatalyst ZnO-Bi2WO6-Ti3C2 prepared through a two-step electrostatic assembly route, which demonstrated high efficiency in degrading the colorless pharmaceutical pollutant ciprofloxacin under natural sunlight irradiation, with a maximum degradation rate of around 77% in 160 minutes. Mechanistic investigation revealed the significant role of MXene in separating photogenerated charges within the photocatalyst.