Ag/GO/Fe3O4/γ-Fe2O3 Nanocomposite for Green-Light-Driven Photocatalytic Oxidation of 5-Hydroxymethylfurfural to 5-Hydroxymethyl-2-furancarboxylic Acid

A novel TiO2/CoFe2O4/SiO2 magnetic nanocomposite was successfully synthesized using sol–gel and hydrothermal methods. This nanocomposite consists of highly dispersed CoFe2O4 and TiO2 nanoparticles on the surface of the SiO2 matrix. The synthesis process involved the utilization of activated carbon, which played a dual role as a support for depositing the CoFe2O4 and TiO2 nanoparticles and as a rigid pattern for producing the silica matrix that enmeshed the nanoparticles. To study the unique characteristics of the samples, a range of analytical techniques, such as FT‐IR, VSM, XRD, SEM, N2 adsorption–desorption analysis, BET and EDX were employed. We carried out a complete examination of the catalytic performance of the TiO2/CoFe2O4/SiO2 nanocomposite for the reduction of different substances, including methyl orange (MO), safranin O (SO), methylene blue (MB), rhodamine B (RhB), chromium (VI) ions, and nitroaromatic compounds such as 2‐nitrophenol (2‐NP), 4‐nitroaniline (4‐NA), 2‐nitroaniline (2‐NA), and 4‐nitrophenol (4‐NP). The findings of our study demonstrate the remarkable efficacy of the TiO2/CoFe2O4/SiO2 nanocomposite in efficiently reducing dyes, Cr (VI), and nitroaromatic compounds to their desired forms in environmentally friendly aqueous solutions. Notably, the nanocomposite stands out due to its simple synthesis process, effortless recyclability, and its convenient separation by a magnet.

Excellent Catalytic Performances of Embedded CoFe₂O₄ and TiO₂ Nanoparticles on the Surface of Silica Matrix Toward Reduction of Toxic Cr (VI), Dyes, and Nitroaromatic Compounds

Zarbakhsh,

Derikvand

2024

Employing Cu@Fe₃O₄/SiO₂@MWCNTs as New Catalyst for the Green Synthesis of New Pyridopyrroloindoles Using Multicomponent Reactions of Isatins

Sheikholeslami‐Farahani,

Hojjati,

Shirangi

et al. 2024

By using a multicomponent reaction involving isatins, diamines or aminoalcohols, activated acetylenic compounds, haloketones, and ammonium acetate in aqueous media in the presence of Cu@Fe3O4/SiO2@MWCNTs as new catalyst, the novel pyridopyrroloindole was produced in high yields. This catalyst was produced by employing Petasites hybridus rhizome water extract as a green media and moderate base. The pyridopyrroloindole derivatives were newly synthesized compounds, and their antioxidant properties were assessed using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical trapping and ferric reducing ability of plasma (FRAP) experiments. The pyridopyrroloindole 6b showed higher performance than butylated hydroxytoluene (BHT) and tert‐butylhydroquinone (TBHQ) better results. This method is used to make pyridopyrroloindole derivatives, and it has the advantages of a quick reaction, high yields, and the ability to separate the products easily.

Bio‐Ag/ZnO@MWCNTs Promoted Green Synthesis of Novel Bis‐Pyrimidothiazines: Evaluation of Biological Activity

Shahvelayati,

Rostami‐Charati,

Shirangi

et al. 2024

This work investigated the one‐pot multicomponent reactions of guanidine, isothiocyanates, and unsaturated 1,3‐dicarbonyl compounds in an aqueous media at room temperature using catalytic quantities of Ag/ZnO@MWCNTs which was produced bis‐pyrimidothiazines with high yields. This field of study uses diphenyl‐picrylhydrazine (DPPH) radical trapping to investigate the antioxidant properties of some generated bis‐pyrimidothiazines. Academic studies that are now in progress have focused on investigating the antibacterial properties of compounds that have been created. An experimental process that produced the bis‐pyrimidothiazines showed a number of noteworthy characteristics, including quick reaction kinetics, high product yields, and simple catalyst separation from the reaction mixture.