Dynamic Piezoelectric Polarization Directs Reaction Pathways in CO 2 Reduction Over Pt/Cu 2 O@BaTiO 3 Dual‐Site Heterostructures

ABSTRACT Efficient and selective CO 2 conversion under mild conditions remains challenging because rapid interfacial charge recombination and poorly controlled carbon‐conversion pathways often limit both catalytic activity and product selectivity. Here, we report a Pt/Cu 2 O@BaTiO 3 (Pt/Cu 2 O@BTO) dual‐site heterostructure in which Pt and Cu 2 O are spatially separated on piezoelectric BaTiO 3 nanorods to establish differentiated interfaces for CO 2 reduction and H 2 O oxidation. Under coupled mechanical stimulation and light irradiation, stress‐induced piezoelectric polarization synergistically enhances interfacial charge separation while promoting CO 2 adsorption and activation at Pt‐related reduction sites. Benefiting from the piezo‐photocatalytic coupling, Pt/Cu 2 O@BTO achieved a CO production rate of 146.7 µmol g −1 h −1 and a CO selectivity of 95.8%. In situ FTIR spectroscopy combined with theoretical calculations reveals that the dynamic piezoelectric polarization not only accelerates charge transport and CO 2 activation, but also redirects the subsequent evolution of key *CO intermediates by making CO desorption more competitive than further hydrogenation. This work demonstrates that dynamic interfacial polarization can simultaneously regulate charge‐transfer behavior and reaction pathways in CO 2 reduction, providing a strategy for selective carbon conversion in multi‐field catalytic systems.