What type of study is this?

This is a In Vitro Study study.

August 21, 2025Open Access

Surface texture dependency of photocatalytic behavior of facile synthesized mesoporous ZnS-ZnO heterostructure under LED illumination

RMRana MahdizadehIran University of Science and Technology PSParvaneh SangpourMaterials and Energy Research Center HEHosein Banna Motejadded EmroozIran University of Science and Technology

Key Points

ZnS demonstrates superior photocatalytic efficiency at 88% degradation of methylene blue, outperforming ZnO and ZnS-ZnO.
Specific surface areas measured for ZnS, ZnO, and their composite were 165 m²/g, 10 m²/g, and 35 m²/g respectively, showcasing significant differences.
Characterization methods included spectroscopy and electron microscopy, ensuring thorough analysis of synthesized materials.
Findings underscore the importance of surface area and charge separation in enhancing photocatalytic processes under LED light.

Abstract

Employing three porous semiconductor particles, the impact of the surface area on dynamic photocatalytic degradation of methylene blue has been investigated under an LED light source. At first, porous ZnS with a relatively high surface area was synthesized via an innovative method in ethanol, which is insoluble for Sulphur precursor (Na2S). This semiconductor was used for the synthesis of porous ZnO and ZnS-ZnO nanocomposites through a simple oxidation treatment in the air atmosphere. The characterization of the synthesized compounds was conducted through different techniques including X-ray diffraction, physisorption of nitrogen, simultaneous thermal analysis, field emission scanning and high-resolution transmission electron microscopy, photoluminescence spectroscopy, FT-IR spectroscopy, Mott-Schottky technique, and visible-ultraviolet spectroscopy. Based on the results, the specific surface areas were reported as 165 m2 g-1, 35 m2 g-1, and 10 m2 g-1 for ZnS, ZnS-ZnO, and ZnO, respectively. Despite ZnS having a higher bandgap (3.3 eV) and lower charge carrier density (9.21⋅1015 cm-3) than ZnS-ZnO, it exhibits better photocatalytic efficiency which emphasizes on the pronounced impact of surface area on the photocatalytic degradation of the selected dye. The efficiency of ZnS in removing organic pollutants is 88%, while ZnO achieves only 43% removal, and the ZnS-ZnO composite exhibits a removal efficiency of 55%. This superior efficiency of ZnS is further supported by its higher surface area, reduced PL intensity and visible-range emissions due to defect states, along with Mott-Schottky analysis confirming trap states that enhance charge separation under LED light. The degradation followed a dynamic process driven by efficient charge transfer and surface interactions.

اسأل الذكاء الاصطناعي

Bookmark

View Full Paper