Natural phenolics and flavonoids modified the hierarchical cellular cellulose sponges for efficient water disinfection

Disinfecting microbially contaminated water in a safe and sustainable way is a great challenge. The phenolics and flavonoids in plants are ideal antibacterial agents for biosafety. Herein, an all-plant-derived antibacterial sponge with a hierarchical cellular structure was prepared from natural phenolic and flavonoid crude extracts and cellulose for water purification. After being modified by quercetin, the quercetin-cellulose sponge (Q-CS) exhibits great toughness, elasticity and a large specific surface area, which benefited from a unique hierarchical cellular structure. Q-CS shows ultrahigh water flux (4.5 × 10 5 L·m −2 ·h −1 ·bar −1 ) and excellent antibacterial abilities against Escherichia coli and Staphylococcus aureus (<1.87 % viability). Sponges modified with crude pyrola (P-CS) and mulberry leaf extracts (M-CS) have similar properties compared with Q-CS. The good performances of P-CS and M-CS show the strong antibacterial applications of natural crude extract. This work provides a strategy for fabricating sustainable and safe antibacterial sponges for water disinfection. • An all-plant-derived hierarchical cellular cellulose sponge is fabricated. • The sponge is tough, elastic and stable because of hierarchical cellular structure. • Phenolics and flavonoids are grafted on cellulose as antibacterial agent. • The sponge shows ultrahigh water flux under 1 bar driving pressure. • The modified sponge has great stable water disinfection ability.