Influence of temperature on the electrochemical and passivation behavior of 2507 super duplex stainless steel in simulated desulfurized flue gas condensates

•Passivation of 2507 stainless steel in desulfurized flue gas condensates is studied.•Oxygen participates in cathodic reaction when the temperature is raised to 60°C.•Higher temperature results in thickening and Cr enrichment of the passive film.•Property of passive film is mainly controlled by film structure and carrier density. Influence of temperature on the electrochemical and passivation behavior of 2507 super duplex stainless steel in the simulated desulfurized flue gas condensates in thermal power plant chimney are investigated. Cathodic reactions are enhanced with temperature, accompanying with the involvement of oxygen reduction when the temperature is raised to 60°C or higher. The unchanged semiconductor type, enrichment of Cr and thickening of the passive film are observed as the temperature increases. The temperature-induced variations of film structure and doping concentrations are responsible for the degradation of protective ability of the passive film.