/manager/Index ${session.getAttribute("locale")} 5 Coupling ferroelectric polarization and anisotropic charge migration for enhanced CO₂ photoreduction /manager/Repository/uon:46850 2 photoreduction into solar fuels is promising for generating renewable energy. Herein, SrBi2Nb2O9 nanosheets are prepared as high-performance photocatalysts for CO2 reduction, highlighting superiority of ferroelectric polarization and anisotropic charge migration. Ferroelectric polarization within SrBi2Nb2O9 nanosheets provides an in-built electric field, which greatly facilitates the bulk charge separation. Also, the photogenerated electrons and holes migrate separately to the NbO6 octahedral layers and within the ab-plane in the Bi2O2 layers, achieving efficient anisotropic charge migration. Without co-catalyst or sacrificial agent, SrBi2Nb2O9 nanosheets show outstanding CO2 reduction activity in producing CH4. The ferroelectric polarization is further enhanced by electric poling and annealing post-treatments. The electrically poled SrBi2Nb2O9 shows a high CH4 evolution rate of 25.91 μmol g−1 h−1 with an AQE of 1.96 % at 365 nm, exceeding most of state-of-the-art photocatalysts reported to date. This work paves an avenue for development of highly efficient photocatalysts and beyond by tuning the ferroelectricity and electronic structure.]]> Mon 29 Jan 2024 18:48:21 AEDT ]]> Ferroelectric polarization promoted bulk charge separation for highly efficient CO₂ photoreduction of SrBi₄Ti₄O₁₅ /manager/Repository/uon:34851 4Ti4O15 as a robust photocatalyst for efficient CO2 reduction. In the absence of co-catalysts and sacrificial agents, the annealed SrBi4Ti4O15 nanosheets with the strongest ferroelectricity cast a prominent photocatalytic CO₂ reduction activity for CH₄ evolution with a rate of 19.8 μmol h−1 g−1 in the gas-solid reaction system, achieving an apparent quantum yield (AQY) of 1.33% at 365 nm, outperforming most of the reported photocatalysts. The ferroelectric hysteresis loop, piezoresponse force microscopy (PFM) and ns-level time-resolved fluorescence spectra uncover that the outstanding CO2 photoreduction activity of SrBi4Ti4O15 mainly stems from the strong ferroelectric spontaneous polarization along [100] direction, which allows efficient bulk charge separation along opposite direction. DFT calculations also disclose that both electrons and holes show the smallest effective masses along a axis, verifying the high mobility of charge carriers facilitated by ferroelectric polarization. This study suggests that the traditionally semiconducting ferroelectric materials that have long been studied as ferro/piezoelectric ceramics now may be powerfully applied in the photocatalytic field to deal with the growing energy crisis.]]> Mon 08 Nov 2021 09:54:09 AEDT ]]>