ZnS Honey-Hump Nanocrystals: Efficient Green Catalysis for Remazol Black Dye Removal in Wastewater Treatment

Abstract

The extensive use of synthetic dyes in a variety of sectors, including textiles, leather, food, and paints are resulted in substantial environmental issues due to their persistence and toxicity in water bodies. Moreover, about twenty to forty gallons of water is used for two pounds of fabric in conventional textile industries around the globe. Hence, it is vital to develop effective and fast catalytic dye removal methods or devices. Citrullus lanatus rind is primarily researched for its effective removal of dye from aqueous solution. The ZnS nanocrystals are well known for its photocatalytic property to remove dyes. In this research, ZnS extracted from the Citrullus lanatus rind was used for investigating the removal of Remazol Black dye. The dye is said to increase heart rate and cause eye problems in humans. The ZnS is extracted using green synthesis and the work focuses on the goal of contributing to long-term and successful water treatment solutions. The generated ZnS nanocrystals were validated using UV–vis spectroscopy, indicating the successful formation of nanoparticles. The presence of polyphenolic groups responsible for reducing metal sulfide nanoparticles was verified using FTIR spectroscopy. Transmission electron microscopy (TEM) research indicated that the produced ZnS nanocrystals had a morphology with a mean size of roughly 6 nm. The impact of nanocrystals in removing Remazol Black dye was examined, with a phenomenal clearance efficiency of 99.8% achieved in 6 min. The rapid and successful dye decomposition was attributable to the chemisorption process, demonstrating ZnS honey-hump-like nanocrystal potential as useful catalysts in ecological cleanup purposes.