Bifunctionalized hybrid silica aerogels for stable low-concentration CO_(2)capture and thermal insulation under humid and high-temperature conditionsOA

To produce a multifunctional silica aerogel with excellent stability under humid and high-temperature conditions,bifunctionalized hybrid silica aerogels(BHSAs)were created by a simple and eco-friendly self-catalyzed sol-gel process.BHSA can be used for thermal insulation and CO_(2)capture with high durability with two functional groups including methyl and amine hybridized.The highest specific surface area(343 m^(2)/g),pore volume(1.66 cm^(3)/g),and surface amine content(2.14 mmol/g)were attained by TMA262 with an appropriate tetraethoxysilane(TEOS)/methyltriethoxysilane(MTES)molar ratio,as well as a water contact angle of 143°.TMA262 demonstrated high CO_(2)adsorption capacity(1.87 mmol/g)and kinetics in humid 1%CO_(2).With a low thermal conductivity at 25℃(0.019 W/(m·K)),TMA262 exhibited outstanding thermal insulation over the temperature range stretching from-100 to 1300℃.Accelerated aging and thermal treatment indicated that TMA262 possessed excellent long-term stability for CO_(2)capture and thermal insulation under humid and high-temperature conditions,and water played a significant role in CO_(2)adsorption capacity.This study seamlessly integrates a diverse array of functionalities within the silica aerogel,offering significant guidance for the advancement of aerogels tailored for multi-scenario applications under extreme conditions.