Polarization‐Reoriented Piezocatalysis Enables Plastic Upcycling with Mechanical Energy

Mixed plastic waste remains difficult to upcycle selectively under mild conditions, and piezocatalysis has been constrained by a persistent see‐saw effect: Stronger piezoelectric polarization tends to divert charge carriers away from the very active sites that drive catalysis. Sha et al. (Nature Communications, 2026) resolve this trade‐off by substituting phosphate into BiOIO ₃ nanorods, creating polarization vacancies that redirect the internal field toward exposed catalytic facets while generating frustrated Lewis acid–base pairs at the resulting I‐O‐P bonding sites. Under ultrasonic stimulation, these sites activate water and generate hydroxyl radicals that drive oxidative reforming of PET, PLA, PE, and their mixtures, achieving over 87% combined H ₂ /CO selectivity and, for PET, a combined methanol/ethanol production rate of 89 mmol g ⁻¹  h ⁻¹ . By establishing polarization reorientation as a general design strategy rather than as a material‐specific fix, this work offers a transferable framework for advancing mechanically driven catalysis toward practical, ambient‐condition plastic upcycling.