Cu@porphyrin-COFs nanorods for efficiently photoelectrocatalytic reduction of CO2

The development of high-performance catalysts for CO2 reduction to hydrocarbons is of great importance for addressing the energy crisis issue. In this work, the Cu@porphyrin-COFs nanorods materials were first designed and synthesized by solvothermal method followed by the electrodeposition of Cu nanowires to the free-base porphyrin-COFs on the carbon fibers. The structure of the free-base porphyrin-COFs were well characterized experimentally and simulatively calculated by DFT method. The Cu@porphyrin-COFs nanorods show high catalytic activity for CO2 reduction under photoelectrocatalytic (PEC) conditions, giving C1-C3 chemicals such as methanol (CH3OH), ethanol (CH3CH2OH), ethane-1,1-diol (CH3CH(OH)(2)) and acetone (CH3COCH3) with an extremely apparent Faradaic efficiency (AFE) of total carbon-based products of 452.75% due to the efficient adsorption of protons onto the surfaces of Cu crystals and excellent absorption of solar light. The (CO2)-C-13 labeling experiments verified that the carbon-based products are derived from CO2. On the other hand, combining with simulation, we show that the hydroxyl groups in free-base porphyrins COFs play a vital role in photoelectrocatalytic reduction of CO2.