Synthesis of silver-doped TiO₂ nanoparticles with highly efficient adsorption of congored

Abstract

TiO₂ nanoparticles (NPs) doped with Ag were produced through a solvothermal method, with varying amounts of silver doping ranging from 0.5% to 1.5%. The samples were analyzed for crystallite sizes, structure, and metallic bondings using XRD, SEM, EDXS, and FTIR techniques. The BET surface areas were determined through nitrogen adsorption isotherms. The efficiency of the silver doped TiO₂ NPs for removing congored (CR) was tested through adsorption experiments. The results showed that the synthesized TiO₂ NPs doped with Ag were uniformly spherical in shape, with tiny average sizes ranging from 7.97 to 12.74 nm and large BET surface areas (98.41-166.1 m² g¹). The silver doped TiO₂ samples with a 0.5% Ag doping amount exhibited the highest adsorption capacity in CR removal, with a maximum adsorption capacity of 454.55 mg of dye per gram of adsorbent and a lower contact time of 20 min than other metal oxide NPs. The CR adsorption onto 0.5% Ag-TiO₂ obeyed the Langmuir isotherm model (R² = 0.989), and the adsorption followed a pseudo second order kinetic equation. The adsorbent could be efficiently reused for five consecutive cycles to remove CR.