Ternary Fe3O4@PANI@Au nanocomposites as a magnetic catalyst for degradation of organic dyes

Magnetic Fe 3 O 4 @PANI@Au nanocomposites are fabricated through electrostatic self-assembly and seed growth methods. The rate constant K app is calculated to be 8.63×10 −3 s −1 at room temperature for the reduction of 4-nitrophenol to 4-aminophenol with an excessive amount of NaBH4 as a model system showing outstanding catalytic efficiency and stability. For recyclable performance, the catalyst exhibits slight loss in catalytic performance on the conversion of 4-nitrophenol after running for more than 10 cycles. Besides, the smaller and simpler the structure, the easier the molecular structure can be degraded, and the faster the cationic dyes can be degraded than the anionic dyes, which can reveal the selectivity. For practical application, Congo red as a pollutant of the lake water is degraded rapidly after Fe 3 O 4 @PANI@Au is added to the solution in a few minutes. It has been demonstrated that magnetic Fe 3 O 4 @PANI@Au nanoparticle composite is a promising catalyst for environment sewage.