The following is an abstract from an article co-authored by Arash Badakhsh, R&D engineer and hydrogen specialist at PNDC. Learn more about Arash in our Meet the Team feature.


Hydrogen (H2) is the lightest known molecule; hence, its compression or liquefaction is highly energy-intensive. One of the promising ways to easily store and transport hydrogen is via the use of chemical carriers such as ammonia (17.8 wt%H2). Synthesis of ammonia, however, accounts for 2% of global energy use and 1.2% of anthropogenic carbon dioxide emissions. So, catalysts play a significant role in mitigating these by lowering the temperature and pressure required for the reaction. In this paper, Arash and his team have studied the fabrication and reactivity of a recyclable catalyst, which offers higher resistance to chemical deactivation. One of the key features in this study is the tunability of the catalyst by ball-milling conditions and exsolution environment. A multi-faceted experimental campaign was carried out, via sophisticated methods such as Atom Probe Tomography, to determine the morphology and the chemistry of the catalyst before and after the reaction.

Bright-field TEM images and EDS mapping of (a) calcined and (b) 12 h exsolved catalysts. The intermediate schematics illustrate the exsolution mechanism.

Read the full article at

Badakhsh, A.; Vieri, H.M.; Yoon, S.P.; Choi, S.H. Exsolved Ru on BaCexOy Catalysts for Thermochemical Ammonia Synthesis. International Journal of Energy Research 2023, 14.