Highly Dispersed Cobalt Centers on UiO-66-NH2 for Photocatalytic CO2 Reduction

Metal–organic frameworks (MOFs) are potential photocatalytic materials for CO2 reduction, however, still limited by their low efficiency. In this work, cobalt decorated UiO-66-NH2 (xCoNU, x presents the mass friction of cobalt) were successfully synthesized through an economic NaBH4 treating method and applied for CO2 photocatalytic reduction. It was confirmed that cobalt worked as the active site in the system, and an optimized CO yielding rate of 1.93 mmol g−1 h−1 in 3 h was achieved on 5CoNU, which is 10.2 times higher than that of UiO-66-NH2. Characterization results revealed that the highly dispersed cobalt in xCoNU accelerates the charge separation and electron transport in the photocatalytic system, improving the photocatalytic CO2 reduction performance. This work provides a simple and convenient method to modify MOFs with metal cocatalyst, and is expected to advance the development of efficient CO2 photoreduction catalysts.Graphical Abstract