Highly Efficient Photoreduction of Low‐Concentration CO 2 to Syngas by Using a Polyoxometalates/Ru II Composite

Abstract At present, the fixation of CO 2 always requires it to be extracted from the atmosphere first, which leads to more energy consumption. Thus, direct photoreduction of low‐concentration CO 2 to useful chemicals (e.g., syngas) under sunlight is significant from an energy‐saving and environmentally friendly perspective. Here, the design and fabrication of a [Ru(bpy) 3 ]/[Co 20 Mo 16 P 24 ] composite is demonstrated for visible‐light‐driven syngas production from diluted CO 2 (3–20 %) gas with a high yield of approximately 1000 TONs (turnover number of syngas). This activity is an order of magnitude higher than the reported system with [Ru(bpy) 3 ] 2+ participation. With evidence from ultrafast transient absorption, GC‐MS, 1 H NMR spectroscopy and in situ transient photovoltage tests, a clear and fundamental understanding of the highly efficient photoreduction of CO 2 by the [Ru(bpy) 3 ]/[Co 20 Mo 16 P 24 ] composite is achieved. Making use of the structure and property designable polyoxometalates towards the photo‐fixation of CO 2 is a conceptually distinct and commercially interesting strategy for making useful chemicals and environmental protection.