CO2 Dominated Bifunctional Catalytic Sites for Efficient Industrial Exhaust Conversion

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.

Automated summary

Photoreduction of exhaust gas from power plant by Ni@TPHH-COF showed appealing yield and selectivity, achieving AQY of 3.96% under 10% CO2 concentration, ranking among the highest reported photocatalysts. The mechanism suggests CO2 plays a dual function, selectively enriching catalytic sites and improving reaction rate.