An Effective Photocatalyticdegradation of Rose Bengal and Eosin Y by Using ZnO Nanoparticles as a Photocatalysts

Abstract

Environmental contamination is the major challenging issue for the advanced and upgrowing countries due to exceptional industrial development. Dyes have played a vital role in global pollution if they are not treated appropriately. In this study heterogeneous photocatalysis process,well-known semiconductor, ZnO nanoparticles (ZnONPs) are used for the degradation of dyesdue to its capability to take part in both acid-base and redox reaction. Precipitation is a highlyeffective and recognized method used to synthesize ZnO NPs, were successfully synthesized and characterized by applying various spectroscopic techniques i.e. XRD, SEM, AFM, ZP, FT-IR, and UV-Visible. Engineered nanoparticles were applied to check their effectiveness on the photocatalytic reduction of dyes, Rose Bengal (RB), and Eosin Y (EY) dyes in the aqueous medium. The catalyst showedpotential photocatalytic efficiency up to 98% RB using 300 µg and >95% EY using 350 µg at 7pH. Dyes degraded completely within 3 minutes under sunlight at maximum absorbance value (λ max) 548and 515 nm, respectively. Moreover, various factors were optimized during degradation protocoli.e. sunlight, irradiation time, reducing agent, power of hydrogen, dyes concentration, and catalyticdose. The elevatedphotocatalyticdegradation efficiencyof both dyes (RB and EY up to 98% wereobserved. Consequentially, the dyes reported in this study specially EY has never been tested before with pure ZnOnanocatalyst hence ZnO NPs can be suggested as a more effectivephotocatalyst for thesuccessful degradation of complex dyes then reported due to their complex structureat the commercial level.