Photo-Electrochemical Application of ZnOG Thin Film for in situ Monitoring of Steel Sour Corrosion

Abstract

Further to traditional corrosion monitoring techniques for rated deteriorations, nowadays modern electrochemical monitoring methods are promising for the control of non-rated damage mechanisms. Considering carbon steel as the most commonly used alloy in the oil and gas industry, there are special grades under NACE MR0175 standard which are immune to sour corrosion. However, according to the industry reports, their immunity can be terminated by upset conditions or on site repairs. This issue will impose either a high operational risk or exorbitant maintenance and inspection costs. Hence, in this paper, a new monitoring technology framework is discussed to lessen a catastrophic failure risk for carbon steel under wet H 2 S corrosion. In this regard, the application of a developed hybridized ZnO-graphene micro-electrode (ZnOG) with a mix band gap of 1.17 eV is studied. Under hydrogen sulfide attack and when ZnOG hybrids are excited by UV illumination, their photoelectrochemical responses are analyzed. ZnOG hybrids emanate informative impedance signals in a response to the formation of ZnO (1x) S x nano-crystals.