The coupled CuO-SnO2 catalyst: Characterization and the photodegradation kinetics towards phenazopyridine

Here, the as-synthesized SnO2 and CuO nanoparticles (NPs) by the hydrothermal procedure were mechanically coupled (SC catalyst). Some characterization techniques including powder X-ray diffraction (PXRD), scanning electron microscope-energy dispersive X-ray analysis (SEM-EDX), diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy were used to brief characterization of the samples. Both PXRD and SEM results confirmed the production of a nano-sized SC sample. The PL intensity was decreased in the coupled SC catalyst. X-ray mapping images confirmed that all constituent elements were homogeneously dispersed through the SC sample. The SC sample showed increased activity in phenazopyridine (PP) photodegradation in an aqueous solution. The activity varied with the change in the SnO2:CuO mole ratio. The highest photodegradation efficiency was achieved at the following conditions: CPP: 5.5 ppm at pH 7, irradiation time: 180 min, SC dosage: 0.8 g L-1. The Hinshelwood model was real for the process, and an apparent first-order kinetics k-value of 0.016 min(-1) (t(1/2)-value of 43 min) was obtained for the PP photodegradation process When COD analyzed the photodegraded PP solutions same k-value was obtained. The HPLC analysis showed a decrease in the main peak intensity at a retention time of 28 min, which corresponds to 89.7% PP photodegradation. The SC catalyst also showed good activity after 3 successive reusing runs. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

Synthesized SnO2 and CuO nanoparticles were mechanically coupled in a SC catalyst, showing increased activity in phenazopyridine photodegradation. The catalyst also maintained good activity after 3 successive reusing runs.