A Nickel Phosphine Complex as a Fast and Efficient Hydrogen Production Catalyst

Here
we report the electrocatalytic reduction of protons to hydrogen
by a novel S2P2 coordinated nickel complex,
[Ni­(bdt)­(dppf)] (bdt = 1,2-benzene­dithiolate, dppf = 1,1′-bis­(diphenyl­phos­phino)­ferro­cene).
The catalysis is fast and efficient with a turnover frequency of 1240
s–1 and an overpotential of only 265 mV for half
activity at low acid concentrations. Furthermore, catalysis is possible
using a weak acid, and the complex is stable for at least 4 h in acidic
solution. Calculations of the system carried out at the density functional
level of theory (DFT) are consistent with a mechanism for catalysis
in which both protonations take place at the nickel center.