Superelastic bio-based polyimide aerogel with excellent oil/water separation performance and effective visible light photocatalytic activity

Aiming to realize sustainable development and reduce environmental pollution, scientists have been on searching for bio-based materials derived from renewable resources to replace petroleum-based materials. Herein, a bio-based polyimide aerogel derived from 2,5-furandicarboxylic acid was synthesized successfully via supercritical fluid drying. The bio-based polyimide aerogel had mesoporous structure and a large specific surface area (220 m2/g), which were highly advantageous to adsorption and photocatalysis. The bio-based polyimide aerogel possessed fast adsorption behavior (within 1 s), outstanding durability (200 cycles of adsorption and desorption), and a self-cleaning property. The bio-based polyimide aerogel could also realize continuous and rapid separation of organic solvent and water with the aid of a vacuum pump. Importantly, the bio-based polyimide aerogel exhibited superelastic (rapid recovery after 90% strain) and anti-fatigue performance (compressive strength remained 96% after 100 cycles). Moreover, the bio-based polyimide aerogel displayed effective photocatalytic activity under visible light. The possible degradation mechanism was also proposed, and radical quenching tests demonstrated that the generation of h+ and ·O2− was the key to photocatalytic degradation. Considering its environmental friendliness and excellent properties, bio-based polyimide aerogel provides a promising solution for oil/water separation and photocatalysis.