Pulsed laser processed FeSiBCuNb glassy alloy with polyphasic nanostructure interactions for efficient degradation of reactive red 195 via photoactivating persulfate

An Fe_73.5Si_13.5B₉Cu₁Nb₃ amorphous ribbon was used as a precursor to fabricate biphasic and polyphasic nanostructure catalysts via pulsed laser processing. The enhancement in nanostructure heterogeneity, light absorption ability, surface hydrophilicity and photothermal conversion of the catalyst resulted in improving photocatalytic performance, evidenced by a higher k value, increased total organic carbon removal rate, and lower ΔE value. The degradation pathway of reactive red 195 molecules in the persulfate system was proposed. Density-functional theory simulations indicated that the excellent catalytic performance of the pulsed laser catalyst was due to its unique polyphasic nanostructure, which induced the reduction in the energy barrier of the rate-determining step (from 2.74 to 1.34 eV) during the conversion of S₂O₈²⁻ to SO₄⁻•. The processed catalyst exhibited an ultrahigh catalytic ability of k_SA•C₀ = 7733 mg·m⁻²·min⁻¹ and strong reusability (28 cycles) without efficiency decay. This study revealed that regulating the nanostructure of the catalyst is an effective strategy to achieve high photocatalytic performance. © 2024 Elsevier B.V.