Green synthesis of reduced graphene oxide/Fe₃O₄/Ag ternary nanohybrid and its application as magnetically recoverable catalyst in the reduction of 4‐nitrophenol

Abstract

Materials having both magnetic and catalytic properties have shown great potential for practical applications. Here, a reduced graphene oxide/iron oxide/silver nanohybrid (rGO/Fe3O4/Ag NH) ternary material was prepared by green synthesis of Ag on pre‐synthesized rGO/Fe3O4. The as‐prepared rGO/Fe3O4/Ag NH was characterized using Fourier transform infrared spectroscopy, X‐ray diffractometry, Raman spectroscopy, vibrating sample magnetometry, transmission electron microscopy and energy‐dispersive X‐ray spectroscopy. rGO sheets were covered with Fe3O4 (8–16 nm) and Ag (18–40 nm) nanoparticles at high densities. The mass percentages were 13.47% (rGO), 62.52% (Fe3O4) and 24.01% (Ag). rGO/Fe3O4/Ag NH exhibited superparamagnetic behavior with high saturated magnetization (29 emu g−1 at 12 kOe), and efficiently catalyzed the reduction of 4‐nitrophenol (4‐NP) with a rate constant of 0.37 min−1, comparable to those of Ag‐based nanocatalysts. The half‐life of 4‐NP in the presence of rGO/Fe3O4/Ag NH was ca 1.86 min. rGO/Fe3O4/Ag NH could be magnetically collected and reused, and retained a high conversion efficiency of 94.4% after the fourth cycle. rGO/Fe3O4/Ag NH could potentially be used as a magnetically recoverable catalyst in the reduction of 4‐NP and environmental remediation.

A chemometric approach based on response surface methodology for optimization of antibiotic and organic dyes removal from water samples

“…The XRD pattern related to magnetic iron oxide nanoparticles shows seven peaks at 21.97, 30.18, 35.64, 42.83, 54.51, 57.15, and 63.09°, confirming the crystalline surfaces (111), (220), (311), (400), (422), (511), and (440) of these nanoparticles. This observation is in good agreement with patterns reported in the literature [ 43 ]. The XRD pattern of the synthesized nanocomposite clearly displays all peaks corresponding to the structures of silver nanoparticles and magnetic nanoparticles.…”

Fungi-Enabled Defect Engineering and Pore Channel Regulation of a Novel Microreactor for Treating Multiple Hazardous Pollutants in One Step

“…Herein, multi-walled carbon nanotubes (MWCNTs)/Fe 3 O 4 /Ag composites were also fabricated in a biomolecular-assisted method as the control. Although with no reports of MWCNTs/Fe 3 O 4 /Ag composites used as a good material for pollutant treatment, the carbon-based/Fe 3 O 4 /Ag composites have been widely used in the field of photocatalysis. − Compared with MWCNTs/Fe 3 O 4 /Ag, PC/Fe 3 O 4 /Ag shows a significant advance in performance. About the same degradation rate can be reached under the condition where only half of the catalyst and hydrogen peroxide were used.…”

From methylarenes to esters: efficient oxidative Csp3–H activation promoted by CuO decorated magnetic reduced graphene oxide

“…These two factors in hybrid materials consisting of magnetic and graphitic nanostructures present an attractive tool for making a heterogeneous graphene-like material. 23 As examples using the adsorption capacity and the separation convenience of the magnetic materials, Wu has reported a new application of Fe 3 O 4 @CuO&GO for the removal of arsenic( iii / v ) from water. 24 Similar to this study, Doan and co-workers have shown that a ternary Fe 3 O 4 /CuO@C composite can be used as a photocatalyst for the degradation of the ciprofloxacin antibiotic.…”