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

• Published in: Applied organometallic chemistry 2017-11, Vol.31 (11), p.n/a
• Main Authors: Thu, Tran Viet, Ko, Pil Ju, Nguyen, To Van, Vinh, Nguyen Thanh, Khai, Doan Minh, Lu, Le Trong
• Format: Article
• Language: English
• Subjects: 4‐nitrophenol; Catalysts; Chemistry; Electron microscopy; Energy transmission; Fourier transforms; Graphene; graphene oxide; Iron oxides; magnetic nanoparticles; Magnetic properties; nanocatalyst; Nitrophenol; Reduction; Silver; Spectrum analysis; Synthesis; X-ray spectroscopy
• ISSN: 0268-2605; 1099-0739
• DOI: 10.1002/aoc.3781

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 superparamagnetic reduced graphene oxide/iron oxide/silver nanohybrid was synthesized using a green method. The nanohybrid efficiently catalyzed the reduction of 4‐nitrophenol and could be magnetically recovered and reused multiple times.