Decoration of 2 H-MoS2 on the surfaces of activated carbon derived from bamboo stem biomass waste: A regenerative novel architecture for effective degradation of methylene blue under natural light

Abstract

The development of visible light-assisted photocatalyst materials is considered a sustainable technology for textile dye pollutant degradation. In this work, a bamboo stem-derived activated carbon/Molybdenum disulfide (AC/MoS2) composite was synthesized using the wet impregnation method. The synthesized AC/MoS2 (5%) (ACM composite) shows enhanced photocatalytic degradation efficiency (98%) for MB degradation within 90 min compared with AC (94%) and MoS2 (33%) under natural light irradiation. FESEM analysis shows the uniform deposition of 2 H-MoS2 on the surface of AC. HRTEM analysis revealed that ACM composite consists of ultra-small activated carbon nanoparticles with a diameter of ∼20 nm and a layered MoS2 with a lateral thickness of ∼150 nm. The effect of catalyst load, pH effect, and MB concentration were evaluated to optimize the photocatalytic activities of AC and ACM composites. The results reveal that the ACM composite possesses high photocatalytic activity with a catalyst quantity of 10 mg at pH 8. Scavenger trapping analysis confirms that hydroxyl radical (•OH) and photogenerated holes (h+) are the main reactive species for photocatalytic degradation of MB. After three cycle experiments, the ACM composite exhibited a slight decrease in the photocatalytic efficiency (89%) and also possesses high stability, which can be regenerated for sustainable photocatalytic material. Moreover, the ACM composite exhibits a long visible absorption range and high structural stability, enhancing the charge separation efficiency of photogenerated electron-hole pairs. This proposed method offers a cost-effective and biomass-derived photocatalyst for the textile wastewater treatment process.