Fabrication of NOTT-220 @I2 via iodine adsorption and immobilization in bismuth organic framework for efficient CO2 photo-reduction

In this research, a kind of bismuth-based metal-organic frameworks—NOTT-220 was investigated as an iodine gas adsorbent. NOTT-220 exhibited good adsorption performance, reaching an adsorption capacity of 955 mg·g−1 at 75 ℃. By various characterization methods and DFT calculations, it was demonstrated that the adsorption process of NOTT-220 included both physical and chemical adsorption, the captured iodine is not only in the form of iodine molecules, but is also converted into BiOI, BiI3 and polyiodide anions. In addition, the adsorbed sample was also used for photocatalytic reduction of CO2, showing better catalytic effect than the original sample. Therefore, the results show that NOTT-220 can not only be used as a promising iodine adsorbent, but also the material after iodine adsorption can be further used for photocatalysis to achieve efficient utilization.