Thermophilic nanozyme with memory effect: distinctive hydrolase mimicry for sustainable polyester microplastic degradation

Mild and efficient degradation of polyethylene terephthalate (PET) waste requires natural PET hydrolases. However, their inherent limitations, such as high cost, poor operational stability, and catalytic working temperatures below the glass transition temperature of PET, urgently necessitate the advancement of highly thermostable systems with thermophilic catalysis performance. Here, we develop a hydrolase-mimicking thermophilic nanozyme using MgAl layered double oxide with the “memory effect”, which exhibits remarkable catalytic activity and structural stability over multiple reuse cycles. Moreover, different from traditional nanozymes that usually require the ·OH radical-involving mechanism for microplastic degradation, the catalytic hydrolysis capability of thermophilic nanozyme originates from abundant Lewis basic sites that activate water molecules to release OH − ions, thereby facilitating the degradation of PET powders and films under mild conditions. By exemplifying the superior degrading performance toward various polyesters and commercial plastic bottle pellets, thermophilic nanozymes provide an effective method for eliminating polyester microplastics with a distinctive hydrolytic degradation process and may inspire future explorations into the structural mimicry of natural hydrolases.