Green hydrothermal synthesis of Aralia elata leaf extracts functionalized Ag/Au nanomaterials and their application

AgNPs and AuNPs typically exhibit special physical and chemical properties, including antibacterial, catalytic, adsorption, optical, and coating properties. Nanomaterials have been widely applied in fields such as biology, medicine, chemical engineering, and new materials. In this paper, the green synthetic chemical method was applied. The leaf extract of Aralia elata could be used as the reducing agent and stabilizer to prepare functionalized nanomaterials, AE-AgNPs, and AE-AuNPs. Green synthesis methods offer advantages such as high cost-effectiveness, simple operation, controllable synthesis conditions, environmental friendliness, pollution-free processes, and the avoidance of highly toxic reagents. Through multiple experiments, this paper had identified the optimal hydrothermal synthesis conditions for AE-NPs. The peak shapes of AE-AgNPs and AE-AuNPs at 445nm and 520nm were confirmed by Uv-vis characterization. SEM and TEM confirmed that both AE-AgNPs and AE-AuNPs exhibited the spherical structure, with average particle sizes of 13.99nm and 14.62nm; EDS confirmed that AE-NPs contained Ag and Au elements; XRD confirmed that AE-NPs contain metallic elemental crystal structures of Ag and Au. TGA indicates that the AE leaf extract on the surface of nanomaterials modifies their structure. FTIR demonstrates that there is a coating layer of AE leaf extract on the surface of NPs. Dye adsorption experiments confirmed that AE-AgNPs and AE-AuNPs have high-efficiency dye removal properties, and the adsorption processes belong to second-order kinetics. The adsorption capacities of AE-AgNPs and AE-AuNPs for MB dye reached 13.26mg·g⁻¹ and 27.47mg·g⁻¹; for SY dye they reached 8.10mg·g⁻¹ and 13.14mg·g⁻¹. MB adsorption process tend to Freundlich multilayer, SY adsorption process tend to Langmuir monolayer. This paper uses the leaf extract of Aralia elata , a natural product, as the raw material to prepare functionalized nanomaterials via green chemical methods, with the prospect of high-value utilization of wild plant resources.