A Multiscale Theoretical Framework of Piezocatalysis

Piezocatalysis, which converts mechanical stimuli into chemical energy, holds significant promise for noninvasive medical therapies. In this process, ultrasonic frequency plays a dual role: it governs both the reaction rate and the electromechanical coupling efficiency, thereby serving as a critical bridge between microscopic and macroscopic physical processes. However, conventional theoretical models lack a multiscale description of coupled physical processes and thus fail to reveal how frequency dictates catalytic activity. Here, we develop an integrated multiscale framework that links, for the first time, macroscopic bubble cavitation dynamics, mesoscopic piezoelectric constitutive relations, and microscopic chemical reaction rate─with ultrasonic frequency as the unifying thread. Our model uncovers the complete frequency-dependent activity profile and elucidates the physical origin of an optimal frequency, predicting a volcano-shaped activity-frequency relationship that agrees well with a range of experimental reports. By reinterpreting piezocatalysis from a multiscale physical field perspective, this work establishes a new theoretical paradigm for the rational design of piezocatalysts.