A new material both for magnetic coupling and electrocatalytic hydrogen production based on a dinuclear nickel(II) complex, [Ni 2 L 4 ] 1 has been prepared by the reaction of NiCl 2 ·6H 2 O and 1-[(2-methoxy) benzene]-3-[2-pyridine] triazene (HL). Magnetic analysis shows that in the solid state this nickel complex exhibits an antiferromagnetic exchange interaction between nickel(II) ions mediated by triazenido-bridges (J = À6.8 cm À1 ).In homogeneous environment, complex 1 shows electrocatalytic activities for hydrogen generation both from acetic acid and neutral buffer with a turnover frequency (TOF) of 101.25 moles of hydrogen per mole of catalyst per hour (mol H 2 /mol catalyst/h) at an overpotential (OP) of 941.6 mV and a TOF of 998.2 mol H 2 /mol catalyst/h at an OP of 836.7 mV, respectively.