Abstract
Efficient electrocatalytic production of H-2 from mixed water/acetonitrile solutions was achieved using three new Co-II complexes supported by the neutral pincer ligand bis(diphenylphosphino)-2,6-di(methylamino)pyridine ("PN3P"). At -1.9 V vs. Fc/Fc(+), these catalysts showed 96% Faradaic efficiency with added water or saturated aqueous saline at rates of up to 316 L(mol cat)(-1) (cm(2))(-1)h(-1) using a glassy carbon working electrode. The complex [Co(kappa(3)-2,6-{Ph2PNMe}(2)(NC5H3)Br-2] (1) was also able to photocatalytically reduce water to hydrogen in the presence of a Ru(bpy)(3)(2+) photosensitizer and a reductant.