Aralia elata leaf extracts synthesize ZnO-based nanoclusters and their dye removal applications

At the nanoscale, various materials exhibit significant changes in their electrical and optical properties, showing optical and electrical performance that is entirely different from that of macroscopic materials, and thus have been widely applied. Among nanomaterials, the zinc oxide nanoclusters (ZnONCs) are commonly applied in the fields of antibacterial and bacteriostatic, photocatalysis, ultraviolet shielding, sensor preparation, and dye removal. In this paper, to reduce the use of toxic and harmful chemical reagents, the leaf extract of Aralia elata was used as the chemical modifier and stabilizer, and the functionalized zinc oxide nanocluster material (AE-ZnONCs) was prepared by the green hydrothermal synthesis method, which can be used for the removal of organic dyes in wastewater. SEM confirmed that the surface of AE-ZnONCs was an irregular lamellar structure, with AE extract adhering to the material surface. The AE-ZnONCs particle size range is 14.16 ~ 52.73 nm, with the average particle size of 31.71 nm. TEM characterization shows that the internal structure of AE-ZnONCs is a layered structure. EDS and XRD confirmed that the nanomaterials contained zinc oxide and AE plant components. TGA characterization confirmed that the mass proportion of AE extract attached to the material surface was 18.3%. BET confirmed that AE-ZnONCs presented a porous structure, with the relative surface area of 69.68 m²/g. AE-ZnONCs could rapidly and efficiently adsorb methylene blue (MB) and sunset yellow (SY) dyes from water; The XRD and SEM analyses have confirmed that the AE-ZnONCs material after the dye adsorption experiment still maintains a stable layered morphology structure, and the hydrothermally synthesized AE-ZnONCs also possesses structural stability. The MB adsorption process follows second-order kinetics and adheres to the Freundlich-type multi-layer adsorption isotherm model. SY adsorption process follows intraparticle diffusion model kinetics and adheres to the Freundlich-type multi-layer adsorption isotherm model. The green hydrothermal preparation method for functionalized zinc oxide promoted advantages such as abundant raw materials, high cost-effectiveness, environmental friendliness, controllable parameters, simple equipment, and easy operation, with broad application prospects.