Template-Free Synthesis of Porous Fe3O4/SiOC(H) Nanocomposites with Enhanced Catalytic Activity

We present a template-free synthesis of Fe 3 O 4 /SiOC(H) nanocomposites with in situ formed Fe 3 O 4 nanoparticles with a size of about 50 nm embedded in a nanoporous SiOC(H) matrix obtained via a polymer-derived ceramic route. Firstly, a single-source precursor (SSP) was synthesized by the reaction of allylhydridopolycarbosilane (AHPCS) with Fe-acetylacetonate [Fe(acac) 3 ] at 140°C. The SSP was heat-treated at 170°C to generate Fe 3 O 4 nanocrystals in the cross-linked polymeric matrix. Subsequently, the SSP was pyrolyzed at 600°C–700°C in argon atmosphere to yield porous Fe 3 O 4 /SiOC(H) nanocomposites with the high BET surface area up to 390 m 2 /g, a high micropore surface area of 301 m 2 /g, and a high micropore volume of 0.142 cm 3 /g. The Fe-free SiOC(H) ceramic matrix derived from original AHPCS is nonporous. The in situ formation of Fe 3 O 4 nanoparticles embedded homogeneously within a nanoporous SiOC(H) matrix shows significantly enhanced catalytic degradation of xylene orange in aqueous solution with H 2 O 2 as oxidant as compared with pure commercial Fe 3 O 4 nanoparticles.