We report here three mononuclear Ni(II) complexes, namely, [Ni(L1)2] (1), [Ni(L2)2] (2) and [Ni(L3)2] (3) where HL1 =1-((4-hydroxybutylimino)methyl)napthalen-2-ol, HL2 = 1-((5-hydroxypentylimino)methylnapthalen-2-ol and HL3 = 1-((6-hydroxyhexylimino)methyl)napthalen-2-ol as the electrocatalyst for hydrogen...