Synergy-Compensation Effect of Ferroelectric Polarization and Cationic Vacancy Collaboratively Promoting CO 2 Photoreduction

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2023-02, Vol.19 (5), p.e2203559
• Main Authors: Li, Shuguan, Chen, Fang, Chu, Shengqi, Zhang, Zeyu, Huang, Jindi, Wang, Shengyao, Feng, Yibo, Wang, Cong, Huang, Hongwei
• Format: Article
• Language: English
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202203559

Photocatalytic CO reduction is severely limited by the rapid recombination of photo-generated charges and insufficient reactive sites. Creating electric field and defects are effective strategies to inhibit charge recombination and enrich catalytic sites, respectively. Herein, a coupled strategy of ferroelectric poling and cationic vacancy is developed to achieve high-performance CO photoreduction on ferroelectric Bi MoO , and their interesting synergy-compensation relationship is first disclosed. Corona poling increases the remnant polarization of Bi MoO to enhance the intrinsic electric field for promoting charge separation, while it decreases the CO adsorption. The introduced Mo vacancy (V ) facilitates the adsorption and activation of CO , and surface charge separation by creating local electric field. Unfortunately, V largely reduces the remnant polarization intensity. Coupling poling and V not only integrate their advantages, resulting in an approximately sevenfold increased surface charge transfer efficiency, but also compensate for their shortcomings, for example, V largely alleviates the negative effects of ferroelectric poling on CO adsorption. In the absence of co-catalyst or sacrificial agent, the poled Bi MoO with V exhibits a superior CO -to-CO evolution rate of 19.75 µmol g h , ≈8.4 times higher than the Bi MoO nanosheets. This work provides new ideas for exploring the role of polarization and defects in photocatalysis.