Synthesis, characterization and electrocatalytic performance of a dinuclear triazenidosilver(I) complex for hydrogen production

Our group has developed a series of molecular electrocatalysts for hydrogen generation based on triazenido-metal complexes (cobalt, copper, etc.). In this paper, we first present the electrocatalytic performance of a new dinuclear silver complex, [Ag-2(L)(2)], formed by the reaction of the triazenido ligand 1-[(2-carboxymethyl)benzene]-3-[(2-methoxy)benzene]triazene (HL) with AgNO3. At room temperature, the silver complex shows photoluminescence at 653nm. The electrocatalytic systems based on this silver complex can afford 106.57 and 1536.36 moles of hydrogen per mole of catalyst per hour from acetic acid at an overpotential (OP) of 991.6mV and from a neutral aqueous buffer (pH=7.0) at an OP of 837.6mV, respectively. Electrochemical investigations show that both silver ion and triazenido ligand play a role in determining the catalytic activities of the electrocatalytic system.