Detaching adhesive oil staining from a surface by water

Using household detergents to clean oil stains has always caused global concerns, as these detergents negatively impact the ecosystem and are toxic. Therefore, it is essential to effectively attenuate the adhesion force between oil stains and substrates to create an easy and detergent-saving cleaning pathway. To address this challenge, we herein develop a strategy to reduce the strength of oil adhesion on common substrates by similar to 20 times through a lamination layer, which contains phase-transitioned lysozyme nanofilm (PTL) and cellulose nanocrystals (CNCs). The resultant CNC/PTL coating significantly enhances the capability of cleaning oil stains in an underwater detergent-free manner; this strategy is applicable to edible oil packaging material and tableware, without impairing the usability and aesthetics of these materials. This coating exhibits excellent mechanical stability and regeneration characteristics through simple soaking, ensuring its robustness in real applications in an infinite life cycle. By eliminating 100% detergent in routine cleaning, the CNC/PTL coating demonstrated remarkable cost-effectiveness, saving 57.7% of water and 83.3% of energy when washing tableware only with water. This work presents an ingenious design to create oil-repellent packaging materials and tableware toward detergent-free water-cleaning pathways, thereby greatly reducing the negative environmental impact of surfactant emissions. This work presents an ingenious design to create oil-repellent packaging materials and tableware toward detergent-free water-cleaning pathways, thereby greatly reducing the negative environmental impact of surfactant emissions. The key point of this report is that the introduction of an amyloid-like phase-transitioned lysozyme intermediate layer into a cellulose nanocrystal coating can rapidly modify any target surface to create a robust underwater oil-repellent state.image