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To retard the spread of fire in many cases with sealing materials is significant. A series of silicone rubber foam materials were prepared with room temperature vulcanization and foaming reactions. The morphology, chemical structure, cell structure, and thermal stability were investigated and results proved that the synthesis of silicone rubber was successful in a wide range of feed ratios. The fire-retardant tests were carried out to study the fire-proof property of the composite materials, and the excellent performance showed a promising prospect for wide application in sealing materials.

ZIF-8 was used as a precursor and was converted to ZnO by calcining at high temperature to remove the organic functional groups therein. Then ZnO@SnO 2 composites were synthesized by hydrothermal method using ZnO as the carrier. All samples were characterized by XRD, SEM, EIS, Transient photocurrent test and Mott-schottky test. The photodegradation effects of pristine ZnO, SnO 2 and ZnO@SnO 2 composites on tetracycline (TC) were evaluated and the best results were obtained (ZnO@SnO 2 = 2 : 1), which could remove 91.2 % of TC under visible light irradiation. The effects of pH, ionic strength, and TC concentration were researched in batch experiments. ZnO@S-nO 2 = 2 : 1 showed favorable photocatalytic activity and stability, including pH and resistance to ionic strength. The enhanced photocatalytic activity of the ZnO@SnO 2 = 2 : 1 composite could be ascribed to the lower recombination probability of electronhole pairs in the heterojunction and the enlarged surface area for TC adsorption during photodegradation. This study provided a reference for heterojunctions with excellent photocatalytic properties.

BiFeO3 is a photocatalyst with excellent performance. However, its applications are limited due to its wide bandgap. In this paper, MIL-101(Fe)@BiOI composite material is synthesized by hydrothermal method and then calcined at high temperature to obtain BiFeO3@Bi5O7I composite material with high adsorption capacity. Among them, An n-n heterojunction is formed, which improves the efficiency of charge transfer, and the recombination of photo-generated electrons and holes prevents the improvement of photocatalytic efficiency and stability. The result of photocatalytic degradation of tetracycline under visible light irradiation showed, BiFeO3@Bi5O7I (1:2) has the best photodegradation effect, with a removal rate of 86.4%, which proves its potential as a photocatalytic degradation material.