Fabricated smart sponge with switchable wettability and photocatalytic response for controllable oil-water separation and pollutants removal

Stimuli-responsive materials with the controllable oil-water separation and water further purification abilities show great potential in practical applications. In this paper, a highly effective and eco-friendly smart pH-responsive melamine sponge with switchable wettability and photocatalytic activity was prepared via anchoring three-dimensional cell-like BiOCl microspheres into sponge skeletons and being modified by dodecanedioic acid and lauric acid. The obtained sponge shows rapidly switchable wettability and can separate various oil/water mixtures with high efficiency up to 99%. Moreover, the as-prepared smart sponge also demonstrates reliable photocatalytic ability and could remove the soluble pollutants (such as methylene blue and Sudan III) under visible light as well as UV light (degradation efficiency around 100%). Besides, the smart pH-responsive material showed satisfactory reusability and stability. This smart multifunctional material has outstanding potential in water resource purification.