Photogenerated Charge Separation in a CdSe Nanocluster Encapsulated in a Metal-Organic Framework for Improved Photocatalysis

Nanoclusters encapsulated in a metal-organic framework (MOF) are the subject of intense interest because of their high promise for photocatalysis. We show computationally that a CdSe nanocluster incorporated into NU-1000 (Cd₆Se₆@NU-1000) allows electron transfer from a visible-light photo-excited organic linker to the lowest unoccupied crystal orbital of the inorganic cluster, which can lead to charge separation. Substituents on the linker can be used to tune the band position and the band gap of the whole composite (Cd₆Se₆@NU-1000), and this makes it possible to perform the water splitting reaction under visible light. The achievement of charge separation within the MOF leads to longer life of the excited states, and as a result, it can enhance the photocatalytic activity of the system.