Pressure induced transformation of methylammonium lead iodide

It is well known that the photovoltaic perovskite, methylammonium lead triiodide, CH3NH3PbI3 (MAPbI3), is one of the most efficient materials for solar energy conversion. Recently we found that a single crystal of this compound could also be a suitable laboratory for studying the chemistry of noble gases. Under high pressure, Ar and Ne interact with MAPbI3 but in different way. Ne stabilizes the high-pressure structure of NexMAPbI3 and prevents amorphization up to 20 GPa. It is remarkable that after releasing the pressure, the crystal has the composition of Ne0.97MAPbI3, which remains stable under ambient conditions. In contrast, above 2.4 GPa, Ar accelerates an irreversible amorphization. The distinct impacts of Ne and Ar have been attributed to differences in their chemical reactivity under pressure inside the restricted space between the PbI6 octahedra.

For more information, read here our published work:

A. Arakcheeva, V. Svitlyk, E. Polini, L. Henry, D. Chernyshov, A. Sienkiewicz, G. Giriat, A. Glushkova, M. Kollar, B. Náfrádi, L. Forro and E. Horváth, Pressure-induced transformation of CH3NH3PbI3: the role of the noble-gas pressure transmitting media, Acta Cryst. (2019). B75, 361-370