CO2 Dominated Bifunctional Catalytic Sites for Efficient Industrial Exhaust Conversion

• Published in: Advanced functional materials Vol. 32; no. 8
• Main Authors: Dong, Man, Zhou, Jie, Zhong, Jun, Li, Hai‐Tao, Sun, Chun‐Yi, Han, Yi‐Dong, Kou, Jun‐Ning, Kang, Zhen‐Hui, Wang, Xin‐Long, Su, Zhong‐Min
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 01.02.2022
• Subjects: Carbon dioxide; Catalytic converters; CO 2 reduction; Conversion; covalent organic frameworks; Economic development; Exhaust gases; Flue gas; Free energy; industrial exhaust photo‐conversion; Materials science; photocatalysis; Power plants; Selectivity; synergic catalysis; Synthesis gas
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202110136

Converting industrial exhaust into valuable chemicals is crucial for sustainable economic development. Direct CO2 photoreduction from real flue gas is an ideal clean and promising way, until now, without success. Here, photoreduction of exhaust gas from the power plant by Ni bridged COF (Ni@TPHH‐COF) is shown. Under visible light, syngas is produced with CO output reaching 2.1 mol kg−1 h−1. The ideal conversion of flue gas is up to 672 L kg−1 h−1. Of note, the system exhibits appealing yield and selectivity under 0.5–40% CO2 and AQY achieves 3.96% under 10% CO2, ranking among the highest value of reported photocatalysts. Mechanism studies suggest CO2 plays a dual function as both a component of a catalytic site and a reactant, which can not only selectively enrich CO2 in catalytic sites but improve reaction rate significantly. This CO2‐dominated bifunctional site prolongs electrons lifetime, stabilizes intermediates, and reduces free energy of reduction under diluted CO2. Ni bridged covalent organic framework layers show efficient photoconversion from the actual industrial exhaust to syngas by CO2 aided bifunctional photocatalytic interface. Under 10% CO2, the apparent quantum efficiency of CO achieves 3.96%. Moreover, the conversion rate of the catalyst to the flue gas could reach 672 L kg−1 h−1 under ideal conditions.