Efficient electro/photocatalytic water reduction using a [NiII(N2Py3)]2+ complex.

The pyridine-rich complex [NiII(LN2Py3)(MeCN)](ClO4)2 (1) acts as an efficient electro- and photocatalyst in the generation of H2 from water. Observed TONs reach 1050 for electrocatalysis and a remarkable 3500 for photocatalysis. Experimental and DFT data support the ligand-reduced [NiILṖ] as the catalytically active species, contrasting with the [CoIL] observed for cobalt catalysts. [ABSTRACT FROM AUTHOR]