X-ray photoelectron spectroscopy analysis of Mo metal surface exposed to sulfate-reducing bacteria

✍ Scribed by Chen, G.; Clayton, C. R.

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 127 KB
• Volume: 27
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/(sici)1096-9918(199904)27:4<230::aid-sia548>3.0.co;2-u

✦ Synopsis

Molybdenum (Mo) is known for its roles in microbial enzymes and in enhancing the corrosion resistance of engineering alloys. In this study, Mo coupons were exposed to a sulfate-reducing bacterial (SRB) culture Desulfovibrio desulfuricans and then changes in surface chemical states were analyzed by XPS and pitting resistance by potentiodynamic polarization in deaerated 0.1 M HCl. Further investigation was conducted using XPS after potentiostatic polarization of the SRB-exposed Mo coupons at Ô160 in deaerated 0.1 M HCl. The samples were mV SCE analyzed with and without the presence of bioÐlm. Control samples were prepared in uninoculated medium. X-ray photoelectron spectroscopy analysis revealed two e †ects : the surface stability of Mo coupon was compromised due to formation during exposure to SRB ; and molybdate formation induced by bacterial production was MoS 2 H 2 S inhibitory to sulfate reduction by forming Mo(V)-S complexes with intermediate sulfur-containing amino groups and proteins. The Mo(V)-S complexes were sparingly soluble and thus protective in the hydrochloric solution.