One-Pot Solvothermal Preparation of Fe₃O₄–Urushiol–Graphene Hybrid Nanocomposites for Highly Improved Fenton Reactions

A new type Fenton-like catalyst was fabricated by anchoring Fe3O4 nanoparticles (NPs) on functionalized graphene oxide (GO) sheets via a simple and environment-friendly reduction route. Urushiol monomers were used to modify GO as well as to stabilize the formed Fe3O4 NPs (∼8 nm). Thanks to the easy cross-link reaction of the urushiol, Fe3O4 NPs strongly anchored on modified GO sheets, giving homogeneous, stable and highly efficient catalyst for Fenton reactions. The generation of the catalytically inactive Fe3+ sludges and the decomposition of H2O2 (to form H2O and O2) during traditional Fenton reactions were also highly inhibited by the urushiol, giving powerful catalytic abilities and excellent cycling performance. By way of example, catalytic degradations of Rhodamine B (RhB) and methylene blue (MB) dyes with the prepared catalyst were dramatically improved from traditional Fenton catalysts. Particularly, the presence of urushiol has led to greater than 90% and nearly full degradations of both dyes within 30 and 60 min, respectively. This catalytic performance was highly stable during the performed 7 cycling tests. By contrast, without the urushiol, catalyst only reached the dye degradation limit of ∼90% over 120 min, and lost more than 60% catalytic ability after 7 cycling uses. We show here not only a novel design of Fenton-like catalyst but also a strategy to anchor metal based catalysts on chemically active substrate for various different applications.