Persulfate-assisted photocatalytic pollutant degradation on ferroelectric BaTiO3/CuFe2O4 material: Ferroelectric polarization enhanced electron transfer and persulfate activation

This study innovatively constructed a polarized ferroelectric BaTiO 3 /CuFe 2 O 4 Z-scheme heterojunction to synergistically enhance quinoline degradation in a persulfate (PS)/photocatalytic system. Comprehensive characterization through ferroelectric analysis and piezoresponse force microscopy (PFM) confirmed the formation of interfacial polarization field in this composite. The polarized VIS/PS/BaTiO 3 /CuFe 2 O 4 * system achieved 99.65 % quinoline removal with excellent cycling stability, outperforming its unpolarized counterpart (83.64 % for VIS/PS/BaTiO 3 /CuFe 2 O 4 ). Mechanistic investigations combined with DFT calculations revealed that the ferroelectric polarization field promoted the directional migration of photogenerated charge carriers through Z-schematic pathway, thereby enhancing charge carrier separation, and it also led to polarized surface sites which improved PS adsorption and activation. The dual enhancement mechanism generated abundant reactive species for efficient quinoline degradation, with intermediate product analysis further clarifying the reaction pathways. This work demonstrates the effectiveness of ferroelectric polarization engineering in optimizing PS-photocatalysis systems, and provides a design strategy for other integrated advanced oxidation technologies in water purification.