Abstract
Photosynthesis in nature uses the Mn4CaO5 cluster as the oxygen-evolving center to catalyze the water oxidation efficiently in photosystem II (PS II). Herein, we demonstrate a bio-inspired heterometallic cluster LnCo3 (Ln = Nd, Eu and Ce) clusters, which can be viewed as synthetic analogs of CaMn4O5 cluster. Anchoring LnCo3 on phosphorus-doped graphitic carbon nitrides (PCN) shows efficient overall water splitting without any sacrificial reagents. The NdCo3/PCN-c photocatalyst exhibits excellent water splitting activity and a quantum efficiency of 2.0% at 350 nm. Ultrafast transient absorption (TA) spectroscopy revealed the transfer of photoexcited electron and hole into the PCN and LnCo3 for hydrogen and oxygen evolution reactions, respectively. DFT calculation showed the cooperative water activation on lanthanide and O-O bond formation on transition metal for water oxidation. This work not only prepares a synthetic model of bio-inspired oxygen-evolving center but also provides an effective strategy to realize light-driven overall water splitting.
Integration of Bio-inspired lanthanide-transition metal cluster and P-doped carbon nitride for efficient photocatalytic overall water splitting
