Effect of substrate hydrophobicity on the electrocatalytic behaviour of phthalocyanine

In this work, the electrocatalytic activity of pyridinoporphyrazine mediator deposited on two substrates with different hydrophobicity has been presented. We focused on hydrophobic highly oriented pyrolytic graphite (HOPG) as well as hydrophilic annealed gold electrode (Au111). The immobilization of mediator has been carried out spontaneous adsorption from aqueous solution on electrode surfaces. The different hydrophobicity surface resulted in change the electrocatalytic activities of mediator to hydrogen in aqueous solution. For this purpose, electrochemical, in situ spectroelectrochemical, and ex situ microscopically characterizations have been performed. The detailed comparison of surface morphology, surface coverage, surface roughness parameters, thickness of deposited layers of mediator, and pH solution has been studied.