Ionic liquids with multiple hydrogen bonds as metal-free catalysts for efficient hydrolysis of PET under relatively mild conditions

Due to the strong hydrophobicity of PET, chemical catalysts usually require harsh conditions. Herein, inspired by the catalytic sites of PETase, we reported a metal-free catalyst with both high stability and activity, which could achieve almost complete hydrolysis of PET (≥ 99%) under relatively mild conditions (100 °C, PH ≈ 8). Mechanistic investigations showed that hydrogen bonds played an important role. With the increase of hydrogen bond multiplicity and strength, the reaction barrier decreased gradually. We believe that this work might provide a direction for the development of efficient metal-free catalysts and have great industrial application prospects. Inspired by the PETase active sites, the designed metal-free catalysts achieved efficient hydrolysis of PET under relatively mild conditions. • Efficient hydrolysis of PET under relatively mild conditions was achieved by using a metal-free catalyst. • The importance of hydrogen bond multiplicity and strength for the reaction was explained clearly. • The design of the catalyst was inspired by the active sites of the PETase. •. CO 2 was used as the cocatalyst, which might have great industrial application prospects.