关键词: MnO₂ , 参比电极, 混凝土, 电极电位

Abstract:

In this work, the solid reference electrode was assemblied by using the electrochemically synthesized manganese dioxide (MnO₂) (EMD) powder, gel electrolyte and thin mortar layer for the durability evaluation of concrete. The EMD reference electrode exhibited higher potential stability (< 10 mV drift) than the chemically synthesied MnO₂ (CMD) based on half year potential tests in the saturated Ca(OH)₂ solution and hardened mortar. In addition, the EMD electrode was almost insensitive to the presences of chloride ion and corrosion inhibitor. Electrochemical impedance and polarization curves indicate that the EMD electrode had lower charge transfer resistance，higher exchange current density and lower temperature coefficient than the CMD electrode. The EMD electrode could be a potential candidate as the long-term reference electrode for the durability management of concrete infrastructure.

Key words: MnO₂ , Reference electrode； Concrete；Electrode potential