| The environmental pollution is more and more serious. Great attention has been paid to the environmental issues arising from Polyvinyl chloride(PVC) plastics. Therefore, the development of degradable PVC plastics becomes an important issue. Photocatalytic degradation of PVC film can not only save energy but also improve economic benefit. Therefore, the synthesis and application of new type photocatalyst have became the focus of research. Niobate silver(AgNbO3) is a kind of perovskite type multifunctional semiconductor materials with forbidden band width of about 2.8 eV. It can absorb more oxygen molecules because there are many oxygen vacancies in the structure, which can take full advantage of solar energy. AgNbO3 can absorb both UV light and visible light, which has a great value in study and broader prospects for development. In this paper, pure PVC film, PVC-AgNbO3 hybrid films and PVC-Fe2O3/AgNbO3 hybrid films were prepared on glass substrates via a coating method, and the photocatalytic degradation behavior of them were investigated. Moreover, the hydrothermal reaction raw materials amount and reaction times were discussed.In this paper, AgNbO3 photocatalyst was prepared by hydrothermal synthesis method The raw materials amount and reaction times were investigated. The experimental results showed that the best raw materials amount were 0.69 g NH4HF2, 0.93 g Nb2O5 and 1.06 g Ag2 O, and the best reaction time was 64 h. The SEM image of the sample with cube-shaped about 1μm.Secondly, PVC-AgNbO3 hybrid films were prepared on glass substrates via a coating method with mass fraction of 0%, 3%, 6%, 9% and 15% of AgNbO3. The photocatalytic degradation experiments were carried out under a UV lamp(6 W, λmax =365 nm) and a xenon lamp(500 W) irradiation. The samples were characterized by X-ray diffraction(XRD), scanning electron microscope(SEM), and fourier transform infrared spectroscopy(FTIR). The results showed that PVC-AgNbO3 hybrid films were degraded under UV light and visible light irradiation. The mass loss of PVC increased with the mass of AgNbO3. The mass loss of PVC-15% AgNbO3 were about 31.75% and 33.83% after irradiation for 120 min under UV light and visible light, respectively. The photocatalytic degradation effect of PVC-AgNbO3 under visible light irradiation was much better than that under UV light irradiation. XRD analysis showed that the AgNbO3 photocatalyst does not change in the photocatalytic degradation process. FTIR analysis showed that PVC-AgNbO3 hybrid films were degraded, producing C=O stretching vibration. That means the PVC-AgNbO3 hybrid films was oxidated by AgNbO3 photocatalyst under light irradiation.Finally, PVC-Fe2O3 /AgNbO3 hybrid films were prepared on glass substrates via a coating method with mass fraction of 0.1%, 0.3%, 0.5%, 0.7% and 0.9% of Fe2O3. We discussed the influence of the Fe2O3 doped amount to PVC-AgNbO3 hybrid film after 120 min under 500 W xenon lamp irradiation. The samples were characterized by XRD, SEM, and FTIR. The results showed that Fe2O3 nanoparticles improved the photocatalytic degradation efficiency of hybrid films. When the mass fraction of Fe2O3 nanoparticles was 0.5%, the degradation efficiency of the hybrid film was the highest, reaching 46.53%. SEM images showed the doping amount of Fe2O3 nanoparticles was 0.5%, the surface of film had the largest holes and the photocatalytic degradation effect of the film was the best. XRD analysis showed that Fe2O3/AgNbO3 composite photocatalyst has promoted the degradation of PVC film under visible light irradiation. FTIR analysis showed that PVC- Fe2O3/AgNbO3 hybrid films were degraded, producing C=O stretching vibration. The stretching vibration intensity enhanced with a subsequent weakened. When the Fe2O3 nanoparticles was doped 0.5% photocatalytic degradation effect of PVC-Fe2O3/AgNbO3 hybrid films was the strongest which consistent with the results of the mass loss.The research provides the basis and direction for the preparation of photocatalytic degradation PVC film, which has the practical significance. |
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