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The endurance limitation related to high coercive fields (${E}_{\text{c}}$) has been one of the substantial challenges to future memory applications of ferroelectric HfO2 films. In this work, we demonstrate a simple, efficient, and accurate method to regulate the ${E}_{\text{c}}$ value of Hf0.5Zr0.5O2 (HZO) films via interface modification through ultraviolet-ozone (UV-O3) irradiation on the surface of bottom electrode. Growth behaviors and ferroelectricity of HZO films were systematically investigated by varying UV-O3 irradiation time. HZO samples show a well-controlled ${E}_{\text{c}}$ upon a suitable UV-O3 irradiation time. Compared with the $w/o$ sample, the ${E}_{\text{c}}$ value of 30-min irradiated sample drops by ~29.5%, and a comparatively high $2{P}_{r}$ of 28.6 $\mu \text{C}$ /cm2 remains. The tuning of ${E}_{\text{c}}$ is clarified to be due to the ratio change of orthogonal and tetragonal phases in HZO films, which can be well controlled by the change of surface energy of the bottom electrode via varying the UV-O3 irradiation time. [ABSTRACT FROM AUTHOR]

Highly efficient and easy recyclable monolithic photocatalysts with ideal separation/transport route for photogenerated charge carriers are much desired. In this work, a ZnO seed‐induced growth approach is developed to fabricate a ternary monolithic photomembrane, that is, ZnS/CdS heterojunction nanorods in situ grow into the interspaces of multilayer reduced graphene oxide (rGO) sheets (denoted as ZnS/CdS/rGO). The monolithic ZnS/CdS/rGO photomembrane can serve as an efficient visible‐light photoactive membrane for photocatalytic (PC) or photoelectrochemical (PEC) hydrogen generation. The fast electron transport of 1D CdS nanorods, the excellent electronic conductivity of multilayer stacked rGO sheets, the intense visible‐light absorption of CdS, the unique hierarchical structure, and double heterojunctions (ZnS/CdS and CdS/rGO) efficiently boost the photogenerated electron‐hole pairs separation and transfer across the interfacial domain of the photomembrane under visible‐light irradiation. Furthermore, the superior stability and reusability of the photomembrane is achieved by the ideal process of photogenerated electron‐hole pair separation/transfer, i.e., holes transfer to ZnS and electrons transfer to rGO to inhibit CdS from photocorrosion. [ABSTRACT FROM AUTHOR]