Dynamic Interface with Enhanced Visible-Light Absorption and Electron Transfer for Direct Photoreduction of Flue Gas to Syngas.

The direct usage of CO 2 in the flue gas to produce fuels or chemicals is of great significance from energy-saving and low-cost perspectives, yet it is still underexplored. Herein, we report the photoreduction of CO 2 from the simulated industrial exhaust by synergistic catalysis of TEOA and a metal-free composite (COF1-g-C 3 N 4 ) fabricated via covalently grafting COF1 with g-C 3 N 4 . The hydrogen bond interaction between TEOA and hydrazine units on COF1 is detected in diluted CO 2 , which leads to significantly enhanced light absorption in the whole visible-light region. Also, the photo-induced electrons undergo fast transfer from COF1 to g-C 3 N 4 . This kind of dynamic interface with enhanced light absorption and electron transfer effects promotes the photosynthetic yield of syngas to 165.6 μmol·g -1 ·h -1 with the use of simulated exhaust gas as a raw material directly. The photosynthetic yield of syngas ranks among the highest of known metal-free catalysts in diluted CO 2 . This work provides a general rule for designing efficient catalysts via a controlled catalytic interface and new insights into the role of TEOA in photochemical CO 2 reduction.