Dual-optimization strategy engineered Ti-based metal-organic framework with Fe active sites for highly-selective CO 2 photoreduction to formic acid

• Published in: Applied catalysis. B, Environmental Environmental, 2023, Vol.327
• Main Authors: He, Xiaoyu, Gao, Xutao, Chen, Xiao, Hu, Shen, Tan, Fangchang, Xiong, Yujie, Long, Ran, Liu, Min, Tse, Edmund C.M., Wei, Fei, Yang, Hong, Hou, Jungang, Song, Chunshan, Guo, Xinwen
• Format: Article
• Language: English
• Subjects: Atomically dispersed Fe sites; Carbon dioxide reduction; High selectivity; Metal-organic frameworks; Visible-light driven photocatalysis
• ISSN: 1873-3883; 0926-3373
• DOI: 10.1016/j.apcatb.2023.122418

Increasing CO 2 conversion efficiency over metal-organic framework (MOF) based photocatalysts is of great significance to promote the carbon capture and utilization. In this work, a dual-benefit design strategy is deployed in the synthesis of a new two-dimensional Fe/Ti-BPDC MOF photocatalyst with atomically dispersed Fe sites. This catalyst demonstrated an excellent catalytic performance in the visible-light-driven CO 2 conversion to HCOOH, achieving a high yield of 703.9 μmol g-1 h-1 at a selectivity greater than 99.7%. This is attributed to the ‘dual-optimization’ achieved by this catalyst to sustain the supply of photogenerated electrons and to effectively activate CO 2 . Specifically, the Fe/Ti-BPDC catalyst provides a high proportion of effective photogenerated electrons for the CO 2 photocatalysis process via a unique electron transfer mechanism. Meanwhile, the strong O/Fe affinity between CO 2 and atomically dispersed Fe active sites not only enables a fast CO 2 activation, but also dictates the intermediate reaction pathways towards high HCOOH selectivity.