Facile synthesis of Collagen/V ₂ CT _x composite aerogel by directional freeze-drying with excellent mechanical strength and oil absorption

Efficient removal of oils has attracted wide attention and researchers have tried to develop effective oil absorbents with increasingly serious oily pollution. Collagen (COL)/V₂C Aluminium Carbide (V₂CT_x) composite aerogels were synthesized using a simple method of blending and directional freezing-drying with original materials of COL and V₂CT_x, in which V₂CT_x MXene was prepared by etching V₂AlC with hydrofluoric acid under stirring at room temperature. Modern testing and analysis techniques were used to characterize the structural properties and surface morphology of the hybrid aerogel. The COL/V₂CT_x composite aerogel shows excellent mechanical properties with 83 kPa compressive stress at 70% strain, low density (about 25 mg/cm³), outstanding thermal stability with 58.67% weight loss from 240℃ to 600℃ and thermal insulation with heat conductivity coefficient 0.05304 W/mK. Importantly, COL/V₂CT_x aerogel exhibits higher oil absorption capacity and stability than that of COL aerogel for various oils. The absorbency of COL/V₂CT_x aerogel for methylene chloride is up to 54 times its weight under Vander Waals forces, intermolecular interaction, and capillary interaction between the aerogel and oily liquids. Therefore, COL/V₂CT_x aerogel possesses a promising application in the field of oil absorption and wastewater treatment.<b>HIGHLIGHTS</b> A novel COL/V₂CT_x aerogel was prepared by a simple method of blending and directional freezing-drying.The absorption capacity of COL/V₂CT_x aerogel for methylene chloride achieves up to 54 times its weight.The COL/V₂CT_x composite aerogel exhibits excellent mechanical properties with 83 kPa compressive stress at 70% strain, low density (about 25 mg/cm³), and good thermal stability with 58.67% weight loss from 240℃ to 600℃.