Switchable Charge‐Transfer in the Photoelectrochemical Energy‐Conversion Process of Ferroelectric BiFeO₃ Photoelectrodes

Abstract

Instead of conventional semiconductor photoelectrodes, herein, we focus on BiFeO3 ferroelectric photoelectrodes to break the limits imposed by common semiconductors. As a result of their prominent ferroelectric properties, the photoelectrodes are able to tune the transfer of photo-excited charges generated either in BiFeO3 or the surface modifiers by manipulating the poling conditions of the ferroelectric domains. At 0 V vs Ag/AgCl, the photocurrent could be switched from 0 μA cm(-2) to 10 μA cm(-2) and the open-circuit potential changes from 33 mV to 440 mV, when the poling bias of pretreatment is manipulated from -8 V to +8 V. Additionally, the pronounced photocurrent from charge injection of the excited surface modifiers could be quenched by switching the poling bias from +8 V to -8 V.

Enhanced Photoelectrochemical Performance of Anodic Nanoporous β-Bi2O3

“…16 Recently, bismuth based ternary oxides such as BiVO 4 , and BiFeO 3 are being actively investigated as promising high efficiency photocatalysts for solar water splitting applications. [17][18][19] However very few research efforts have been focused on understanding photo electrochemical behavior of the binary bismuth oxide which is the building block for the more advanced complex bismuth based oxides.Bismuth oxide (Bi 2 O 3 ) exists as six different polymorphs depending on the synthesis route and thermal treatment. These polymorphs are a) α -monoclinic, b) β -tetragonal, c) γ -body centered cubic, d) δ -face centered cubic, e) ε -orthorhombic and f) ω -triclinic.…”

“…16 Recently, bismuth based ternary oxides such as BiVO 4 , and BiFeO 3 are being actively investigated as promising high efficiency photocatalysts for solar water splitting applications. [17][18][19] However very few research efforts have been focused on understanding photo electrochemical behavior of the binary bismuth oxide which is the building block for the more advanced complex bismuth based oxides.…”

Recent Advances in Bismuth‐Based Nanomaterials for Photoelectrochemical Water Splitting

“…[99] By poling pretreatment, the orientation of bending at the BiFeO 3 /electrolyte can be switched from upward to downward to promote water oxidation and the reduction reaction. [99] By poling pretreatment, the orientation of bending at the BiFeO 3 /electrolyte can be switched from upward to downward to promote water oxidation and the reduction reaction.…”

“…[99] By poling pretreatment, the orientation of bending at the BiFeO 3 /electrolyte can be switched from upward to downward to promote water oxidation and the reduction reaction. [99] Attemptst o fabricate BiFeO 3 films by an efficient CVD technique mainly by using aerosol-assisted and low-pressure CVD techniques have also been reported. Thea uthors have also used surface modifierss uch as dyes and CdSe quantum dots.…”

Enhanced Charge Transfer by Passivation Layer in 3DOM Ferroelectric Heterojunction for Water Oxidation in HCO3−/CO2 System

“…In this regard, for the first time, we demonstrate a novel 3D ordered macroporous (3DOM) ferroelectric heterojunction composed of BiFeO 3 (BFO) and LiNbO 3 (LN) as a photoanode for water oxidation in HCO 3 − /CO 2 system. BFO has a relatively narrow bandgap (≈2.1 eV) as a great lighter harvester in a wide wavelength coverage, which has been used as an efficient photocatalyst in water splitting. Then LN has the highest Curie temperature (1140–1210 °C) and largest spontaneous polarization (0.65–0.78 C m −2 ) .…”