Facile Synthesis and Characterizations of Mixed Metal Oxide Nanoparticles for the Efficient Photocatalytic Degradation of Rhodamine B and Congo Red Dyes

Abstract

Photocatalytic degradation has been suggested to be a cheap and efficient way to dispose of organic pollutants, such as dyes. Therefore, our research team strives to produce nanophotocatalysts in a simple and inexpensive way. In this work, the Pechini sol–gel technique was employed for the facile synthesis of Mn0.5Zn0.5Fe2O4/Fe2O3 and Fe0.5Mn0.5Co2O4/Fe2O3 as mixed metal oxide nanoparticles for the efficient photocatalytic degradation of Rhodamine B and Congo Red dyes. XRD, FT-IR, a N2 adsorption/desorption analyzer, EDS, FE-SEM, and an UV–Vis diffuse reflectance spectrophotometer were used to characterize the produced samples. The XRD patterns revealed that the average crystallite size of the Fe0.5Mn0.5Co2O4/Fe2O3 and Mn0.5Zn0.5Fe2O4/Fe2O3 samples is 90.25 and 80.62 nm, respectively. The FE-SEM images revealed that the Fe0.5Mn0.5Co2O4/Fe2O3 sample consists of cubic and irregular shapes with an average diameter of 1.71 µm. Additionally, the Mn0.5Zn0.5Fe2O4/Fe2O3 sample consists of spherical shapes with an average diameter of 0.26 µm. The energy gaps of the Fe0.5Mn0.5Co2O4/Fe2O3 and Mn0.5Zn0.5Fe2O4/Fe2O3 samples are 3.50 and 4.3 eV and 3.52 and 4.20 eV, respectively. In the presence of hydrogen peroxide, the complete degradation of 100 mL of 20 mg/L of Rhodamine B and Congo Red dyes occurred at pH = 8 and 3, respectively, within 50 min, using 0.1 g of the synthesized samples.

Facile synthesis and characterization of magnesium and manganese mixed oxides for the efficient removal of tartrazine dye from aqueous media

“…In the case of increasing the temperature, the organic substances were easily removed, and a small crystallite size of mixed oxides was obtained. 35 …”

“…In the case of increasing the temperature, the organic substances were easily removed, and a small crystallite size of mixed oxides was obtained. 35 Fig. 1 X-ray diffraction patterns of the G500 (A), G700 (B), and G900 (C) samples.…”

“…There was no carbon in the G700 and G900 samples because 700 and 900 °C were sufficient for complete liberation of organic substances. 35 Fig. 3A-C represents the SEM images of the G500, G700, and G900 samples, respectively.…”

“…because the amount of gases released during the liberation of organic substances increases with increasing temperature. 35 Fig. 4A-C represents the N 2 adsorption/desorption isotherms of the G500, G700, and G900 samples, respectively.…”

“…This method is straightforward, requires low-cost materials, and controls the morphology and crystallite size of nanoparticles. [33][34][35] This method succeeded in preparing many nanomaterials such as a-Fe 2 O 3 , CuO/Li 3 BO [36][37][38][39][40][41][42][43] However, the world needs more low-cost nanomaterials to get rid of the problem of water pollution. To achieve this goal, our research group has synthesized MgMn 2 O 4 /Mn 2 O 3 and MgMn 2 O 4 /Mn 2 O 3 /Mg 6 MnO 8 as novel nanostructures using the Pechini sol-gel method.…”