One-pot synthesis of ZnO/oligoaniline nanocomposites with improved removal of organic dyes in water: Effect of adsorption on photocatalytic degradation

ZnO nanoparticles supported on hierarchical oligoaniline microstructures were synthesized in one pot at ambient condition. The ZnO/oligoaniline nanocomposites were characterized by SEM, TEM , XRD , FTIR, TG/DTA, and physical adsorption of nitrogen. The adsorption and photocatalytic efficiency of the resulting materials were evaluated for removal of dyes. The adsorption data for dyes removal met pseudo-second-order kinetic model. The role of adsorption on photocatalysis was investigated under different reaction conditions. Simultaneous adsorption and photocatalysis (SAP) emerged enhancing effect on cationic dyes, while equilibrium adsorption followed by photodegradation (EAP) improved the catalytic rate of anionic dye. The apparent first-order model was chosen as kinetic equation to estimate photocatalytic reaction. Under SAP mode, ZnO/oliganiline nanocomposite exhibited a higher catalytic rate compared to pure ZnO nanoparticles for dyes photodegradation. The incorporation of oligianiline support significantly enhanced the photocatalytic efficiency of ZnO nanoparticles.