Corrosion behavior of SiC coated HX with MoSi2 interlayer to be utilized in iodine-sulfur cycle for hydrogen production

Zain Hussain; Zuhair S Khan; Asif Hussain Khoja; Altamash Shabbir; Abdulaziz Al-Anazi; Israf Ud Din

doi:10.1016/j.heliyon.2023.e21640

Corrosion behavior of SiC coated HX with MoSi₂ interlayer to be utilized in iodine-sulfur cycle for hydrogen production

Heliyon. 2023 Nov 2;9(11):e21640. doi: 10.1016/j.heliyon.2023.e21640. eCollection 2023 Nov.

Authors

Zain Hussain¹, Zuhair S Khan², Asif Hussain Khoja¹, Altamash Shabbir¹, Abdulaziz Al-Anazi³, Israf Ud Din⁴

Affiliations

¹ U.S.-Pakistan Centre for Advanced Studies in Energy (USPCAS-E), National University of Sciences and Technology (NUST), Sector H-12, Islamabad, 44000, Pakistan.
² Office of Research Innovation and Commercialization (ORIC), University of Wah, Wah Cantt, 47010, Pakistan.
³ Department of Chemical Engineering, College of Engineering, King Saud University, P. O. Box 800, Riyadh, 11421, Saudi Arabia.
⁴ Chemistry Department, College of Science and Humanities, Prince Sattam bin Abdulaziz University, P.O. Box 173, Alkharj, 11942, Saudi Arabia.

Abstract

In this era, renewable energy technologies are suitable to meet the challenges of fossil fuel depletion and global warming. Thus, hydrogen is gaining attention as an alternative clean energy carrier that can be produced from various methods, one of them is the iodine-sulfur (I-S) cycle which is a thermochemical process. The I-S cycle requires a material that can withstand an extremely corrosive environment at high temperatures. Immersion tests were conducted on bare superalloy Hastelloy X (HX), MoSi_2, and SiC-MoSi₂ coated HX, deposited in physical vapor deposition (PVD) to evaluate their corrosion resistance. Bare HX exhibited a high corrosion rate of 208.1 mm yr^-1 when exposed to 98 wt% sulfuric acid at 300 °C. In contrast, HX with MoSi₂ coating showed a much lower corrosion rate of 23.5 mm yr^-1, and HX with SiC-MoSi₂ coating demonstrated the lowest corrosion rate at 6.5 mm yr^-1 under the same conditions. The coated samples were analyzed via FESEM before and after corrosion testing. The FESEM images reveal the formation of coalescent particles on the surface of the coating. The elemental analysis illustrates an increased concentration of silicon and oxygen in the corroded samples. Elemental mapping of these samples show a uniform distribution of elements over the sample. These findings contribute not only to materials science understanding but also to practical applications in hydrogen production via the I-S cycle, where corrosion-resistant materials are critical.

Keywords: Corrosion resistance; Hastelloy X; Iodine sulfur cycle.