Efficient homogeneous electrocatalytic hydrogen evolution using a Ni-containing polyoxometalate catalyst

Compound K 2 [Ni(H 2 O) 6 ] 2 [V 10 O 28 ]·4H 2 O ( 1 ) exhibits homogeneous electrocatalytic HER in an aqueous solution with a turn over frequency of 2.1 s −1 and effectively low overpotential of 127 mV at pH 2.3.