Core-shell Prussian blue analogues@ poly(m-phenylenediamine) as efficient peroxymonosulfate activators for degradation of Rhodamine B with reduced metal leaching.

Herein, Prussian blue analogues@poly(m-phenylenediamine) nanoparticles (PBA@PmPDs) with well-defined core-shell structure were synthesized. The successful coating of poly(m-phenylenediamine) (PmPD) on the surface of FeCo [Co(CN)] (Fe-Co-Co PBA) was confirmed by SEM, TEM, XRD, TGA, FT-IR and XPS. The catalytic performance of Fe-Co-Co PBA@PmPDs was evaluated by activation of peroxymonosulfate (PMS) for degradation of Rhodamine B (RhB), the effects of different influence factors on the RhB degradation efficiency were investigated, including PMS concentration, temperature, initial solution pH, and co-existing inorganic salts. Cobalt ions leaching and stability of the catalysts were studied, Co ions concentration dissolved into the solution from the solid catalysts at 60 min is reduced by half after the Fe-Co-Co PBA is coated with PmPDs. The RhB removal efficiency is higher than 90% even after four cycles and the nanoparticles still maintain the core-shell structure, indicating that Fe-Co-Co PBA@PmPDs is stabile and reusable. Radical quenching experiments and electron paramagnetic resonance spectra indicate that both SO and OH are generated during the PMS activation process and SO is the dominant reactive species. In virtue of its superior catalytic activity, excellent reusability and stability, low metallic ion leaching, Fe-Co-Co PBA@PmPDs could be a promising catalyst for the remediation of contaminated water.