Efficient Ba/Ti-doped g-C3N4 nanosorbent for improved adsorption and selective lead abolition

Herein, an advanced composite consisting of Ba-TiO₂ nanoparticles grown on layered g-C₃N₄ sheets was synthesized through a facile sol-gel-based Pechini method and characterized using scanning and transmission electron microscopy, X-ray Diffraction, Fourier-transformed infrared spectroscopy, X-ray photoelectron microscopy. Due to its large surface area (≈99 m²/g), the composite exhibited high adsorption ability towards Pb⁺² reaching up to 450 mg / g where the adsorption kinetics complied with the pseudo-second-order model and the Langmuir and Freundlich isotherms well described the adsorption equilibrium. The composite exhibited high selectivity for the Pb⁺² adsorption over the Cu⁺², Zn⁺², Ni⁺², Co⁺², and Cd⁺² ions along with five rounds of regeneration and recyclability. Cation−π interaction, pore diffusion, –NH₂, and –OH bonding was postulated as a mechanism for the Pb⁺² ions adsorption. These findings validated that the Ba-TiO₂ nanoparticles/ g-C₃N₄ (BaTiCN) composite was a potential composite for the scavenging of heavy metals in water systems.