Photocatalytic degradation of ethylene by mesoporous nano silica loaded chlorin e6

Abstract

Green foods are usually harvested and stored before ripening, but excessive ethylene generated during storage can lead to the loss of vegetables and fruits. Photocatalytic oxidation provides a promising method to remove ethylene and extend the shelf life of green foods. In this study, a mesoporous nanosilica-loaded Ce6 composite nanomaterial (Ce6@SiO2) was designed and synthesized to adsorb ethylene into its pores and then degrade it under visible light illumination. The photosensitizer Ce6 in the mesopore produced large amounts of reactive oxygen species that degraded ethylene. The specific surface area was greatly increased by coating the material on the surface of a sodium alginate (SA) hydrogel membrane. This improved its degradation efficiency and facilitated the adsorption and degradation of ethylene during fruit storage. The ethylene removal capacity was studied by measuring the ethylene concentration and increases in the humidity in Tedlar gas bags. Practical applications were tested by observing color changes and surface decay of tomatoes stored with and without SA/Ce6@SiO2. The results showed the system may be used in practical commercial preservation systems.