Photo-assisted mineralisation of titan yellow dye using ZnO nanorods synthesised via environmental benign route

Abstract

Green synthesis of metal oxide nanoparticles using plant extract is a most promising substitute for regular methods that involve chemical synthesis approach. The present study reports the synthesis of ZnO nano rods (ZNRs) using Calotropis gigantea, a plant rich in flavonoids and alkaloids and their application as a photocatalyst in the degradation of titan yellow dye. The synthesized ZNRs were characterized using XRD, FESEM–EDS and HRTEM-SAED. The XRD results confirm the formation of wurtzite ZnO. The FESEM images confirmed that ZNRs have length ranging from 20 to 200 nm, diameter ranging between 20 and 80 nm and width between 20 and 50 nm. The bio-synthesized ZNRs were used for photo-degradation of titan yellow dye, one of the main effluents from textile industries, discharged directly into water bodies. The ZNRs exhibited 95% dye degradation for 10 ppm TY dye concentration in the presence of 60 mg of the ZNRs catalyst at pH 8 for 60 min UV irradiation. The present study reports eco-friendly method for the synthesis of ZNRs and its efficiency as a photo catalyst in the advanced photo assisted oxidation process for degradation of titan yellow dye.