Sunlight‐induced Photocatalytic Degradation of Methylene Blue Dye by Magnesium and Silver‐based Cadmium Sulfide Nanoparticles

Abstract

The photodegradation activity of nanomaterials is generally studied and used for water purification purposes. The present investigation reports the synthesis of magnesium and silverbased cadmium sulfide nanoparticles (Mg 2 Ag 2 CdS 4 NPs) with a size of ∼ 25 nm for the degradation of methylene blue (MB) dye. The optical properties of the nanoparticles were studied, and the bandgap energy of the nanoparticles was found to be 2.16 eV. The photocatalytic degradation showed the highest photocatalytic activity (88 %) for 90 min. The effects of operating parameters such as the amount of catalyst, initial pH, and the initial dye concentration were studied. The rate constants for various doses were calculated and followed the pseudo-first order. A 75 % degradation of MB dye was found even after five uses. The photocatalyst can significantly contribute to the removal of hazardous toxic chemicals from aqueous solutions from an environmental point of view.[a] J.

Fabrication of Carbon‐Based ZnBi2S4 and ZnBi2Se4 Nanocomposites for Photocatalytic and Electrochemical Applications

“…[42] The peak of the water molecule can be seen at 3515 cm À 1 because of the OÀ H stretching band. [43] A noticeable rise in Figure 2(b) at 500-700 cm À 1 indicates the presence of vibrations that stretch the metal selenium bond. [44] CÀ H stretching vibrations are assigned to the 1354 cm À 1 band.…”

“…where C 0 and C t are concentration at the beginning and at a certain time, t is the irradiation time. [43] Synthesis of Zinc-Bismuth Chalcogenide/Carbon nanocomposites Zinc-Bismuth Chalcogenide/Carbon nanocomposites were synthesized by chemical methods. 1 mmol of zinc (II) nitrate hexahydrate (Zn(NO 3 ).6H 2 O) and 1 mmol of bismuth (III) nitrate pentahydrate (Bi(NO 3 ) 3 .5H 2 O) were added to 10 mL of oleylamine in a 100 mL three-neck flask connected to a Schlenk line.…”

“…Oxygen and photoelectrons can be employed to prevent hole-electron pairs from recombining. [51] The dissolved oxygen is converted to superoxide anion (•O 2 À ) radicals by the free electrons. The dye molecules are degraded by these light-generated radicals into simple molecules like CO 2 and H 2 O (Scheme 2).…”

“…In contrast, the negatively charged nature of alkaline solutions draws cationic dyes and promotes adsorption. [43] The alkaline medium, however, slowed the degradation of anionic dyes. The ideal pH for methylene blue, rhodamine B, and methyl orange in an aqueous solution for the photocatalytic degradation of dyes, respectively, was determined to be 9 and 5, respectively.…”

“…Equation (7) has been used to determine the specific capacitance of the fabricated nanostructured electrode from the CV curve. [51] C…”