Synergy of ferroelectric polarization and oxygen vacancy to promote CO2 photoreduction

Solar-light driven CO2 reduction into value-added chemicals and fuels emerges as a significant approach for CO2 conversion. However, inefficient electron-hole separation and the complex multi-electrons transfer processes hamper the efficiency of CO2 photoreduction. Herein, we prepare ferroelectric Bi3TiNbO9 nanosheets and employ corona poling to strengthen their ferroelectric polarization to facilitate the bulk charge separation within Bi3TiNbO9 nanosheets. Furthermore, surface oxygen vacancies are introduced to extend the photo-absorption of the synthesized materials and also to promote the adsorption and activation of CO2 molecules on the catalysts' surface. More importantly, the oxygen vacancies exert a pinning effect on ferroelectric domains that enables Bi3TiNbO9 nanosheets to maintain superb ferroelectric polarization, tackling above-mentioned key challenges in photocatalytic CO2 reduction. This work highlights the importance of ferroelectric properties and controlled surface defect engineering, and emphasizes the key roles of tuning bulk and surface properties in enhancing the CO2 photoreduction performance. Solar-driven CO2 reduction into value-added chemicals and fuels is attracting worldwide attention. Here, substantially enhanced photocatalytic CO2 reduction activity is achieved via the synergy of surface oxygen vacancies and ferroelectric polarization over Bi3TiNbO9 photocatalyst.

Automated summary

In this study, significantly enhanced photocatalytic CO2 reduction activity is achieved through the synergy of surface oxygen vacancies and ferroelectric polarization over the Bi3TiNbO9 photocatalyst. This highlights the importance of ferroelectric properties and controlled surface defect engineering in enhancing the CO2 photoreduction performance.