Co-Al Layered double hydroxides decorated with CoFe2O4 nanoparticles and g-C3N4 nanosheets for efficient photocatalytic pesticide degradation

Abstract In this work, composite photocatalysts containing cobalt-aluminum layered double hydroxides (Co-Al LDH), graphitic carbon nitride (g-C 3 N4), and cobalt ferrite (CoFe 2O4) were prepared and applied for the photocatalytic degradation of chlorpyrifos (CP) as a model agricultural pollutant. The Co-Al LDH/g-C 3 N4-CoFe 2O4 composites showed enhanced photocatalytic activity compared to g-C 3 N4, due to the improved separation of photo-generated electrons and holes. 97.2% of CP was degraded during the photocatalytic process in the presence of the Co-Al LDH/g-C 3 N4-CoFe 2O4 photocatalyst. Almost complete degradation of CP was achieved under visible light irradiation, the photocatalytic activity of the composite was also dependent on the CP concentration, pH, and photocatalyst amount. A mathematical model incorporating these parameters was developed through response surface methodology, allowing optimized photodegradation of CP. The photo-oxidation of CP followed a pseudo-first-order kinetic model.