Optimized Eco-Friendly Synthesis and Characterization of Citric Acid and Urea- Functionalized Nanographene-Encapsulated Copper Nanocomposite Coatings by Hydrometallurgical Methods

This study presents a novel method for synthesizing citric acid and urea-encapsulated nanographene with embedded copper nanoparticles (۲۰–۱۰۰ nm diameter, BET surface area ۲۶۰ m².g-۱), utilizing density functional theory (DFT) modeling. The process involves hydrometallurgical encapsulation using low-cost materials. Citric acid and urea create covalent amide bonds between the carboxyl groups of polycitric acid and the amino groups of urea, enhancing electrostatic interactions and ensuring uniform dispersion in water, while maintaining spontaneous pH stability (۱.۸ to ۲.۰) without external acids, thus addressing aggregation and stability challenges in traditional graphene-copper composites.The method consists of two steps: i) dissolving the nanocomposite precursor (۱.۰–۲.۵ g.L-۱ functionalized nanographene with ۰.۳ g CuSO₄ via ultrasonication) and ii) controlled electrolytic deposition on high-purity copper substrates. The dissolution step evaluates nanocomposite concentration, while the electrolytic step examines parameters such as current density, electrolyte pH, and electrode spacing. Key parameters include a current density of ۰.۰۱ A.dcm-۲, a voltage of ۳ V, and an anode-cathode distance of ۱.۵–۳.۵ cm, achieving maximum efficiency at ۲۰–۳۰% electrolyte concentration.Characterizations confirm successful functionalization and encapsulation: FT-IR spectroscopy shows peaks at ۱۷۰۸ cm⁻¹ for C=O and ۳۴۰۰–۳۵۰۰ cm⁻¹ for NH₂; SEM/EDS reveals a uniform morphology with ۱۷.۹۹ wt% Cu and ۴۵.۳۶ wt% O, providing superior oxidation barriers. DFT elucidates mechanisms, showing an energy gap reduction from ۴.۱۷ eV to ۲.۶۶ eV in the optimal B-II configuration, enhancing reactivity and electron transfer, insights absent in previous methods.

کلیدواژه ها:

Biofunctionalized nanographene ، copper encapsulation ، mechanical improvements ، Electrical conductivity ، hydrometallurgical deposition ، DFT modeling (PBEPBE/DGDZVP)