Comparative Study of Sonophotocatalytic, Photocatalytic, and Catalytic Activities of Magnesium and Chitosan-Doped Tin Oxide Quantum Dots

Abstract

The present study demonstrates the hydrothermal synthesis of SnO2 quantum dots (QDs) doped with different concentrations (2, 4 wt %) of magnesium (Mg) and a fixed amount of chitosan (CS). The obtained samples were investigated through a number of characterizations for optical analysis, elemental composition, crystal structure, functional group presence, interlayer spacing, and surface morphology. The XRD spectrum revealed the tetragonal structure of SnO2 with no significant variations occurring upon the addition of CS and Mg. The crystallite size of QDs was reduced by incorporation of dopants. The optical absorption spectra revealed a red shift, assigned to the reduction of the band gap energy upon doping. TEM analysis proved that the few nanorod-like structures of CS overlapped with SnO2 QDs, and agglomeration was observed upon Mg doping. The incorporation of dopants little enhanced the d-spacing of SnO2 QDs. Moreover, the synthesized nanocatalyst was utilized to calculate the degradation percentage of methylene blue (MB) dye. Afterward, a comparative analysis of catalytic activity, photocatalytic activity, and sonophotocatalytic activity was carried out. Notably, 4% Mg/CS-doped QDs showed maximum sonophotocatalytic degradation of MB in basic medium compared to other activities. Lastly, the prepared nanocatalyst was found to be efficient for dye degradation in any environment and inexpensive.

Surface functionalized silver-doped ZnO nanocatalyst: a sustainable cooperative catalytic, photocatalytic and antibacterial platform for waste treatment

“…Many technologies have been established for the degradation of these kinds of water pollutants, such as biodegradation, electrochemical techniques, adsorption (physical), and chemical 10 . In the past few years, metal oxide NPs mediated photocatalysis under UV-Vis light has gained significant attention for degrading synthetic dyes in a wet environment 11 . Over conventional methods that have used harmful oxidants and/or facilitated partial dye degradation, photocatalysis offers an effective and eco-friendly route of dye contamination removal instead of simply transforming them into another phase 12 .…”

“… 10 Over the past few years, metal oxide NP-mediated photocatalysis under ultraviolet-visible (UV-vis) light has gained significant attention for degrading synthetic dyes in a wet environment. 11 Over conventional methods that require the use of harmful oxidants and/or facilitated partial dye degradation, photocatalysis offers an effective and eco-friendly route toward dye contamination instead of simply transforming the dye into another phase. 12 Photocatalysis is initiated by photons in UV light that excite electrons (e − ) in the valence band (VB) of the photocatalyst that then move to the conduction band (CB) and generate holes (h + ).…”

La-Doped CeO2 Quantum Dots: Novel Dye Degrader, Antibacterial Activity, and In Silico Molecular Docking Analysis

“…The emission band of CeO 2 was observed at 414 nm . CeO 2 QDs exhibited higher intensity allocated to fluorescence phenomena, which indicates a low electron transfer efficacy . The substitution of La into QDs reduced the intensity, which verified the low recombination rate of excitons, and the intensity was further diminished by addition of higher concentration of La, which was assigned to phosphorescence phenomena .…”

Facile Synthesis of Vanadium Oxide/Carbon Spheres-Doped Nickel Oxide Functioned as a Nanocatalyst and Bactericidal Behavior with Molecular Docking Analysis

“…63 As NSs have a high surface-to-volume ratio, facilitating effective dye reduction, their size is another factor influencing the CA. 64 The The literature review and the current experiment study for the reduction of MB can be seen in Table 1. Significant CA against MB dye was observed upon the higher incorporation of catalysts.…”