3100 pc spectrophotometer

The structure of the product was characterized by a Rigaku X-ray diffractometer (XRD) (RINT 2200, Japan) with CuKα (λ = 1.5418 Å) radiation with a step interval of 0.02° s⁻¹. The morphological analysis was carried out by a field emission scanning electron microscope (FESEM) (JEOL JSM 7001F microscope) at an accelerating voltage of 15 kV and a transmission electron microscope (TEM) (JEOL JEM 2100F microscope) at an accelerating voltage of 200 kV. UV-vis spectroscopy analyses were performed by a Shimadzu 3100 PC spectrophotometer (Japan). X-ray photoelectron spectroscopy (XPS) was performed by a Shimadzu ESCA 3400 (Japan).

The photocatalytic properties of synthesized samples were examined by the photo-assisted degradation method using rhodamine blue (RhB) as a model dye, at room temperature under a xenon light source (MAX-303, Asahi Spectra) as a source of visible-light irradiation. Before light irradiation, the RhB solution was prepared by adding 2 mg dye in 100 mL DI water, then a known amount of photocatalyst was added and the mixture was stirred under the dark condition to stabilize and equilibrate the adsorption of RhB onto the surface of the catalyst. The reaction mixture was then allowed to stir under the visible lamp which was positioned at 15 cm above the reaction mixture. At regular time intervals, 6 mL of the suspension was collected, centrifuged, and analyzed by a UV-vis spectrometer (Shimadzu 3100 PC spectrophotometer, Japan). The degradation of RhB was quantified from the decrease in the intensity of the associated characteristic absorption. The photodegradation percentage of RhB was calculated using the following equation:where C₀ and C_t are the concentrations of RhB at time 0 and t (s), respectively, and t is the irradiation time. The catalyst was regained by centrifugation and re-dispersed in the RhB solution for the recycling tests.