Synthesis and evaluation of chlorinated polypropylene-hematite fibrous matrices for enhanced photocatalytic oxidation of methylene blue

This study aims to develop an efficient matrix-photocatalyst system that will eliminate existing problems in photocatalytic oxidation systems. For the first time, chlorinated polypropylene (PP-Cl) was used as the polymeric matrix in a photocatalyst system, and PP-Cl fibers with a diameter of 3.3 ± 0.4 µm were prepared by electrospinning. The presence of chloride ions enhanced photocatalytic degradation efficiency by generating additional reactive oxygen species. Hematite particles of approximately 50 nm were synthesized by thermal decomposition and showed weak antiferromagnetism. These nanoparticles were added to the PP-Cl fibrous matrix using electrospinning, electrospraying, and spin-coating techniques. Methylene blue (MB) was nearly completely degraded by PP-Cl/hematite matrices within 60–90 min under visible light. The amount of hematite in each matrix was calculated as approximately 0.45 mg/cm², 0.75 mg/cm², and 27 mg/cm² for the electrospun, electrosprayed, and spin-coated PP-Cl/hematite matrices, respectively. Although the electrospun matrices contain fewer hematite nanoparticles than the others, the MB degradation time was shorter due to the more homogeneous distribution of nanoparticles in the matrix. Additionally, this matrix-photocatalyst system is stable and recyclable; it maintains catalytic activity with negligible loss even after five cycles, demonstrating its potential for cost-effective environmental cleanup processes.