Giant Charge\nSeparation-Driving Force Together with\nUltrafluent Charge Transfer in TiO<sub>2</sub>/ZnFe-LDH Photoelectrode\nvia Ferroelectric Interface Engineering

Hydrogen fuel production using photoelectrochemical (PEC)\nwater-splitting\ntechnology is incredibly noteworthy as it provides a sustainable and\nclean method to alleviate the energy environmental crisis. A highly\nrapid electron shuttle at the semiconductor/WOC (water oxidation cocatalyst)\ninterface is vital to improve the bulk charge transfer and surface\nreaction kinetics of the photoelectrode in the PEC water-splitting\nsystem. Yet, the inevitably inferior interface transition tends to\nplague the performance enhancement on account of the collision of\nhole–electron transport across the semi/cat interface. Herein,\nwe address these critical challenges via inserting ferroelectric layer\nBTO (BaTiO<sub>3</sub>) into the semi/cat interface. The embedded\npolarization electric field induced by ferroelectric BTO remarkably\npumped hole transfer at the semiconductor/WOC (TiO<sub>2</sub>/ZnFe-LDH)\ninterface and selectively tailored the electronic structure of LDH\nsurface-active sites, leading to overwhelmingly improved surface hole\ntransfer kinetics at LDH/electrolyte interface, which minish the electron–hole\nrecombination in bulk and on the surface of TiO<sub>2</sub>. The TiO<sub>2</sub> nanorods encapsulated by ferroelectric-assisted ZnFe-LDH\nachieve 105% charge separation efficiency improvement and 53.8% charge\ninjection efficiency enhancement compared with pure TiO<sub>2</sub>. This finding offers a strategic design for electrocatalytic-assisted\nphotoelectrode systems by ferroelectric-pumped charge extraction and\ntransfer at the semiconductor/WOC interface.