Synthesis of Ag doped SiO2-TiO2 aerogels with nano-sized microcrystalline anatase structure through IL control

[摘要] In this paper, Ag doped SiO2-TiO2 aerogels with nano-sized microcrystalline anatase structure through a sol-gel way, ionic liquid(IL), 1 - butyl-3-methylimidazole bromide ([bmim]Br), is used as a structure control agent. The catalysts were characterized by SEM, XRD and nitrogen adsorption-desorption isotherms (BET analyses). The photocatalytic activities were investigated by degration of active brilliant blue under UV-light. It was demonstrated that IL facilitate the formation of mesoporous and anatase microcrystalline structure at around ambient condition, without calcination. Both at sol-step and gel-step, the concentration of IL aqueous solution prominently effected on the structure properties of catalysts. Surface area, crystalline grain dimension and mecroporous structure all played important roles in the degradation reactions. The catalyst with 1/10 Si/Ti ratio, 385.2 m2g-1surface area and 6.2nm crystalline grian size, showed excellent photocatalytic degradation rate up to 99.7%.

[发布机构] School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian; 116034, China^1

[关键词] Ambient conditions;Anatase structures;Crystalline grains;Degradation reaction;Microcrystalline structures;Nitrogen adsorption desorption isotherms;Photo catalytic degradation;Without calcination