title: Controllably Interfacing with Ferroelectric Layer: A Strategy for Enhancing Water Oxidation on Silicon by Surface Polarization.
abstract: Silicon (Si) is an important material in photoelectrochemical (PEC) water splitting because of its good light-harvesting capability as well as excellent charge-transport properties. However, the shallow valence band edge of Si hinders its PEC performance for water oxidation. Generally, thanks to their deep valence band edge, metal oxides are incorporated with Si to improve the performance, but they also decrease the transportation of carriers in the electrode. Here, we integrated a ferroelectric poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] layer with Si to increase the photovoltage as well as the saturated current density. Because of the prominent ferroelectric property from P(VDF-TrFE), the Schottky barrier between Si and the electrolyte can be facially tuned by manipulating the poling direction of the ferroelectric domains. The photovoltage is improved from 460 to 540 mV with a forward-poled P(VDF-TrFE) layer, while the current density increased from 5.8 to 12.4 mA/cm(2) at 1.23 V bias versus reversible hydrogen electrode.
authors.affiliation: Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University , 199 Ren'ai Road, Suzhou, Jiangsu 215123, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cui
authors.affiliation: Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University , 199 Ren'ai Road, Suzhou, Jiangsu 215123, China.
authors.forename: Zhouhui
authors.initials: Z
authors.lastname: Xia
authors.affiliation: Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University , 199 Ren'ai Road, Suzhou, Jiangsu 215123, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Wu
authors.affiliation: Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University , 199 Ren'ai Road, Suzhou, Jiangsu 215123, China.
authors.forename: Fengjiao
authors.initials: F
authors.lastname: Chen
authors.affiliation: Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University , 199 Ren'ai Road, Suzhou, Jiangsu 215123, China.
authors.forename: Yanguang
authors.initials: Y
authors.lastname: Li
authors.affiliation: Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University , 199 Ren'ai Road, Suzhou, Jiangsu 215123, China.
authors.forename: Baoquan
authors.initials: B
authors.lastname: Sun
keywords: dipole; ferroelectric; photoelectrochemical; silicon; surface polarization; water oxidation