Heterogeneous sonocatalytic degradation of anazolene sodium by synthesized dysprosium doped CdSe nanostructures

Abstract

Undoped and Dy-doped CdSe nanoparticles are synthesized and then characterized by the SEM, XRD, FT-IR, XPS and BET methods, which verify successful preparation of the doped catalyst. The sonocatalytic degradation of anazolene sodium as a model azo dye is higher than sonolysis process and the 2% Dy-doped CdSe with band gap of 1.42eV exhibits the greatest sonocatalytic performance. The decolorization efficiency (DE%) of sonocatalysis with 2% Dy-doped CdSe, undoped CdSe and sonolysis after 90min of the process is 91.32%, 56.13% and 39.14%, respectively. In addition, the sonocatalytic degradation of anazolene sodium increases with enhancement of the dopant, catalyst dosage, ultrasonic power, dissolved gasses and decreasing of initial anazolene sodium concentration. Furthermore, with addition of chloroform, sulfate, chloride and ethanol as the radical scavengers, the DE% decreases indicating the controlling mechanism of free radicals for the dye degradation. Besides, the results reveal the appropriate reusability of the catalyst and various degradation by-products are identified using the GC-MS technique. Eventually, the empirical kinetic model is expanded by nonlinear regression analysis for prediction of pseudo first-order constants in various operational conditions.

Fabrication, functionalization and performance of doped photocatalysts for dye degradation and mineralization: a review

“…Indeed, heterogeneous photocatalysis has been employed for the degradation of different dyes (Wang et al 2010; Barbosa et al 2015;Al-Kahtani and Abou Taleb 2016;Ajmal et al 2016) by virtue of the greenness traits emanating from the unique morphologies and outstanding physico-chemical characteristics of the novel photocatalysts. Yet, the relatively high economic costs associated with the novel photocatalysts (Fan et al 2016;Lin et al 2017), the wide energy band gaps (Fang et al 2015;, low adsorption capacity (Khataee et al 2018; and poor reusability seem to pose certain limitations to their wide use and full-fledged application in large-scale photocatalytic dye remediation processes.…”

Facile synthesis of SnO2 2D nanoflakes for ultrasound-assisted photodegradation of tetracycline hydrochloride

“…The enhanced removal of TcH under sonophotocatalytic system may be ascribed to the sonoluminescence effect (Sheydaei et al 2019). Typically, the presence of semiconductor material (catalyst) in an ultrasound-aided system generates enormous electron-hole pairs that object to decompose the target molecules (Khataee et al 2018). Hence, the order of different experiments in terms of its performance was sonophotocatalysis (80%) > photocatalysis (45%) > sonophotolysis (27%) > photolysis (15%).…”

Sonochemistry in nanocatalysis: The use of ultrasound from the catalyst synthesis to the catalytic reaction

“…These results have been explained by the effects of mechanochemical energy or micromixing and emulsification effects, both provided by cavitation [40]. Some recent examples also reported the use of heterogeneous nanocatalysts for environmental remediation applications, testing their sonocatalytic [41][42][43][44][45] and sonophotocatalytic activities [46] for the degradation of pollutants in liquid effluents. In these recent examples, low ultrasonic frequencies have been used allowing the reduction of treatment times.…”