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Fe3O4@PVA microcapsule catalyst with dissolution as trigger condition was synthesized by utilizing nano Fe3O4 catalyst as core material and water-soluble polyvinyl alcohol as shell material. The microcapsule catalyst was loaded in poly(lactic-co-glycolic acid)(PLGA) membrane to prepare the freshwater/seawater degradable Fe3O4@PVA/PLGA composite films.Transmission electron microscopy (TEM) and dynamic light scattering (DLS) particle size distribution were used to test the morphology of Fe3O4@PVA. The shell thickness of Fe3O4@PVA core-shell particles is 2-3 nm. The structural characteristics, magnetic and mechanical properties of Fe3O4@PVA core-shell particles and Fe3O4@PVA/PLGA composite membrane were determined by FTIR, XPS, TG, VSM and electronic universal material tests. The degradation properties of Fe3O4@PVA/PLGA composite films in freshwater, seawater, air, darkness and low temperature environments were discussed. The results show that the maximum degradation ratio of Fe3O4@PVA/PLGA composite films is 97.79% at 120 days in seawater and 99.75% at 120 days in freshwater. Fe3O4@PVA/PLGA composite films are degraded in the seawater and the mass average molecular weight decreases from 28440 to 1396.

In order to prepare highly efficient and environmentally friendly photocatalysts, polyvinyl alcohol nanofibers coated with Al-doped ZnO precursor (AZO) were prepared via electrospinning and hydrothermal synthesis. Furthermore, AZO hollow nanofibers were successfully fabricated after calcination at high temperature. The morphology, structure and properties of the samples were characterized by scanning electron microscopy, X-ray diffractometer, X-ray photoelectron spectrometer, thermogravimetric analyzer and UV spectrophotometer. The results show that AZO hollow nanofibers have good photocatalytic degradation of dye.