Photodegradation of acid orange 7 from aqueous solution under visible light irradiation using nanosized ZnO/chitosan/graphene oxide composite

摘要

ABSTRACT Present study reports the preparation of nanosized ZnO/chitosan/graphene oxide (ZnO/Ch/GO) composite via hydrothermal procedure. The characterisation was carried out by FT-IR, X-ray diffraction (XRD) and scanning electron microscopy (SEM). X-ray diffraction (XRD) analysis confirmed the crystalline nature of Wurtzite ZnO with orientation in (100), (002), (101), (102), (110), (103), (200) and (112) planes at 31.9, 34.4, 36.6, 47.9, 56.9, 62.7, 66.1 and 69.2º values. The results show that ZnO with high purity and uniform size distributed in chitosan and graphene oxide. The composite behaviour was investigated for the removal of Acid Orange 7, as pollutant model, using the photodegradation activity. The effect of parameters such as pH (3–9), composite amount (0.008, 0.01, 0.015, 0.02, 0.025 g), dye concentration (10, 15, 20, 25, 30 ppm) and contact time (15, 30, 45, 60, 75, 90, 105 min) were studied. The results showed that dye removal under visible light irradiation using ZnO/Ch/GO composite was 97.5%. The kinetic analysis has shown that photodegradation mechanism obeys from pseudo-first-order model.