Liquid hydrogen carriers play a significant role in diversifying the energy supply pathways by trans-porting hydrogen on a large scale. Those molecules need to undergo fast and total decomposition. Thus, in our studies, amorphous carbonaceous materials, alone and decorated with a metal active phase, have been employed for hydrogen production via ammonia splitting. We propose the non-thermal plasma (NTP) environment due to its effectiveness in the process. The adsorption and splitting of ammonia over carbons and carbon-supported catalysts (Ni, Mo), dif-fering in the chemical structure of surface functional groups, have been investigated by in-situ spec-tral studies directly under NTP conditions. As a result of NH3 physical and chemical sorption, surface species in the form of ammonium salts, amides, and imides decompose immediately after switching on the plasma environment, and new functionalities are formed. Carbon catalysts are very active for NH3 splitting. The determined selec-tivity to H2 is nearly 100% on N-doped carbon materials. The data obtained indicate that the tested materials possess excellent catalytic ability for the economical production of COx-free hydrogen from NH3 at low temperatures. The decoration of carbon surface with non-noble metals shows superior catalytic activity in NH3 cracking. Moreover, it has been found that nitrides form during the process, resulting in an increase in yield. This has led to the conclusion that metal nitrides may be viable catalysts in the ammonia decomposition process. In general, the mechanism of catalytic decomposition is based on the fact that there exist two types of nitrogen atoms on the surface of metal nitride: native and adsorbed nitrogen. As the native nitro-gen is involved in the overall process, there are a few possible combinations for the desorption of N2 molecules: both atoms may derive from ammonia dissociation – the Langmuir-Hinshelwood mecha-nism. Both atoms may be native surfaces, or the atom that comes from the dissociation can be com-bined with the native surface N atom, according to the Mars-van Krevelen scheme. Our team recently demonstrated that carbonaceous materials (i.e., those with or without an active metal phase) can be effectively harnessed as catalysts for hydrogen production. We stated that the reaction occurs due to the innate H-resistivity and N-affinity of carbon materials. These key factors shift the equilibrium to the product, which allows almost 100% conversion. Moreover, the process is performed only on the surface and does not interfere with the C-structure, which means the used C-catalysts are highly stable. Acknowledgements This work was supported by the Polish National Science Centre (NCN) grant OPUS 25 no. 023/49/B/ST11/01341.

Research interests:

– ¬open mind for interesting topics concerning investigations of surface chemistry

– reaction mechanisms investigations under plasma- and catalytic enhancement plasma- environment

– synthesis & physicochemical properties studies and applications of new nanostructural adsorbents and catalysts.

– spectroscopic investigations of surface chemistry changes during adsorption and catalysis using, among others, in-situ FTIR techniques.