First-principles study of Iridium oxide desorption from iridium low-index surfaces at high temperature

Iridium is one of the noble metals. Although iridium has good chemical inertness and mechanical properties especially at high temperature, iridium has a problem to use, due to the desorption problem[1]. It is known that desorption occurs mainly the form of IrO3 molecule below 1775K[2]. To investigate about iridium desorption problem, theoretical understanding of iridium surface oxide is needed.
In this study, we investigate surface oxide of low-index iridium surface, such as Ir(100), Ir(110), and Ir(111) to find energetically favorable surface oxide by using first-principles calculations based on density functional theory. Also we use a thermodynamical approach, we can find energetic difference between the low temperature and high temperature.

[1] H. Jehn (1978), Platinum Metals Rev. 22, (3), 92-97
[2] John H. Carpenter (1989), Journal of the Less-Common Metals 152, 35-45