Superhydrophobic starch-based nanocomposite cryogel for oil removal underwater and magnetically guided oil slick cleanup

Abstract

Low-cost and eco-friendly carbohydrate-based absorbents have attracted great attention for cleaning oil spill that poses a serious threat to the ecosystem. Porous starch-based materials have been proven to have good oil absorption performance, but the hydrophilicity of these materials limits their application in oil spill cleanup. Herein, a novel starch-based superhydrophobic absorbent (HMS-SiO2@MSC) was achieved by introducing nanoparticles into starch cryogel. Fe3O4 and silylated SiO2 nanoparticles endowed the adsorbent with magnetism (saturation magnetization: 4.36 emu/g) and superhydrophobicity (water contact angle: 154.4°), respectively. In addition, the surface chemical composition and microstructure of the adsorbent were investigated in detail. Some crucial properties of HMS-SiO2@MSC were also comprehensively confirmed, including water-repellent, self-cleaning, anti-fouling, and durability. Furthermore, HMS-SiO2@MSC exhibited good practicability of removing oil underwater and magnetically guided cleaning oil slick on the water surface. This work provided a new carbohydrate-based adsorbent, which would broaden the application fields of starch.