Nd(III) removal from aqueous solutions using GO/ZnO nanocomposites: an experimental and computational study
OPEN CHEMISTRY, cilt.24, sa.1, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 24 Sayı: 1
- Basım Tarihi: 2026
- Doi Numarası: 10.1515/chem-2025-0270
- Dergi Adı: OPEN CHEMISTRY
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CAB Abstracts, Directory of Open Access Journals
- Dokuz Eylül Üniversitesi Adresli: Evet
Özet
In this study, graphene oxide/zinc oxide (GO/ZnO) nanocomposite was synthesized for the removal of Nd(III) ions from aqueous solutions. GO was prepared using a modified Tour method, while ZnO nanoparticles were synthesized via the hydrothermal method. The adsorption mechanism highlights through computational modelling, incorporating Quantum Theory of Atoms in Molecules- Non-Covalent Interactions (QTAIM-NCI) and ELF analyses, underscores the potential of GO/ZnO as an effective adsorption system for Nd(III). Detailed DFT calculations, including density of states (DOS), non-covalent interaction analysis, reduced density gradient (RDG) iso-surface, and electron localization function (ELF) analysis have been performed to provide insights into the nature and types of the interactions responsible for the stability of GO/ZnO and the charge transfer processes occurring on the surface of the complex. The nanocomposite was characterized for the morphology, surface chemistry, and functional groups relevant to the Nd(III) adsorption process. Adsorption experiments were conducted at room temperature, optimizing parameters such as pH, initial metal ion concentration, and contact time to maximize Nd(III) removal. The adsorption process was well described by the Langmuir isotherm and followed pseudo-second-order kinetics. The mechanism of the adsorption process was determined from Weber-Morris and Boyd models. The findings suggested that the diffusion rate-limiting process of adsorption was the external mass transport attributed to both the intraparticle and film diffusion. The GO/ZnO nanocomposites exhibited a maximum adsorption capacity of 186.42 +/- 3.12 mg/g for Nd(III) ions. Post-adsorption analyses using X-ray photoelectron spectroscopy (XPS) and SEM-EDX confirmed the chemisorption of Nd(III) on the GO/ZnO surface. Thermodynamic demonstrated the spontaneity, endothermic nature, and temperature favor of the adsorption of Nd(III) ions on GO/ZnO. Additionally, density functional theory (DFT) calculations were employed to study the adsorption mechanism, providing insights into the configuration and adsorption energy of Nd(III) on GO/ZnO. These results highlight GO/ZnO nanocomposite as a promising candidate for efficient neodymium ion removal from aqueous environments.