Enhanced performance of lanthanum orthoferrite/chitosan nanocomposites for adsorptive photocatalytic removal of Reactive Black 5

New lanthanum orthoferrite (LaFeO 3 )/chitosan nanocomposites were synthesized with different chitosan loadings (15 and 35%). Their adsorptive photocatalytic activity in the removal of Reactive Black 5 (RB5) was studied by manipulating the pH of the RB5 solution (pH 3, pH 6, pH 9), the catalyst loading (1 g L −1 , 2 g L −1 , and 3 g L −1 ), and the initial concentration of RB5 (30 mg L −1 , 50 mg L −1 , and 70 mg L −1 ) under 100 W LED light. The nanocomposites have a nanocrystalline structure similar to LaFeO 3 with a lower S BET and P V but a higher P R . The LaFeO 3 was distributed well on chitosan matrices with variations in the elemental composition. The band gap was gradually decreased with increased chitosan loading. The nanocomposite with 15% chitosan loading (LC15) resulted as the most prominent photocatalyst with the highest removal of RB5 up to 98.5% under experimental conditions of pH 6, 2g L −1 of catalyst loading, and 30 mg L −1 of initial RB5 concentration. The LC15 showed good stability, wherein the degradation efficiency was more than 90% after the fifth cycle with no significant change in the chemical properties. This work provides a technique to improve the removal of recalcitrant dyes through the processing of adsorptive photocatalysis utilizing adsorbent and perovskite.