Facile synthesis of heterogeneous CdO-NiO nanocomposite with efficient photocatalytic activity under visible light irradiation

Abstract

A NiO/CdO nanocomposites was fabricated using precipitation deposition method. The as-prepared photocatalyst was generally characterized by various spectral techniques like XRD, SEM, EDAX, UV-DRS, FT-IR, TEM and BET spectral techniques. The synthesized nanocomposite of CdO/NiO were used in the removal of Rose Bengal (RB) as a model organic pollutant under the irradiation of visible light. The XRD pattern of the composite resulted in the cubic CdO and NiO diffraction peaks. EDX spectrum confirms the presence of the elements Cd, Ni and O in the composite. The optical response for the composite showed the presence of separate adsorption signature for CdO and NiO in the visible region at about 510 nm and 380 nm respectively. Among the as-prepared nanocomposites the one of 5% CdO/NiO displays the best photocatalytic activity of the degradation. Various parameters like photocatalyst stability, Catalyst dosage, pH and initial dye concentration were investigated. The investigations of the adsorption kinetics and isotherm shows the adsorption process with pseudo-first- order kinetics by Langmuir adsorption isotherm. The synthesized catalyst has the capacity for the enhancement thereby opening up a new opportunities in various areas in photocatalysis.

Keywords

• CdO-NiO
• Nanocomposites
• Rose bengal
• Photodegradation and visible light