. Plasma-surface coupled modelling of N₂-H₂ DC discharges for ammonia production

POSTER

Abstract

In this work we present the ongoing validation of a kinetic model for nitrogen-hydrogen plasmas, leveraging complementary modeling and diagnostic analyses, highlighting the significance of plasma-surface interactions in ammonia production. We model cylindrical DC glow discharges (10’s cm long and ∼ 1 cm inner radius), produced in N2-H2 gas mixtures (0 − 100% H2 concentrations), at 0 − 600 sccm flows, p = 10 − 700 Pa pressures, and Idc = 5 − 100 mA discharge currents [1]-[6]. Simulations use the LisbOn KInetics (LoKI-B+C) simulation tool [7, 8], comprising an electron Boltzmann equation solver (LoKI-B) and a chemical solver (LoKI-C), adopting an updated version of the kinetic scheme for volume mechanisms in [9], complemented by a mesoscopic kinetic model for plasma-surface interactions inspired in [6]. Diagnostics use electric measurements, mass spectrometry, OES, and FTIR spectroscopy. We observe good qualitative agreement between simulations and measurements. Simulation results confirm that the main production mechanisms of NH3 occur at the surfaces (Langmuir-Hinshelwood and Eley-Rideal recombinations), while the main destruction mechanism is due to collisions with the N2(A) metastable. The validation effort will continue, focusing on improving the agreement between model results and the experimental measurements.

References

[1] Chatain, A. et al., Plasma Sources Sci. Technol. 32, 035002 (2023).

[2] Brovikova, I. N. and Galiaskarov, E. G. High Temperature, 39, 809–814 (2001).

[3] Cernogora, G. et al., J. Phys. B: Atom. Mol. Phys. 14, 2977 (1981).

[4] Popa, S. et al., Journal de Physique III 7, 1331-1337 (1997).

[5] Amorim, J. et al., J. Phys. D: Appl. Phys. 68, 1915-1917 (1996).

[6] Gordiets, B. et al., Plasma Sources Sci. Technol. 7, 379–88 (1998).

[7] Tejero-del-Caz, A. et al., Plasma Sources Sci. Technol. 28, 043001 (2019).

[8] https://github.com/IST-Lisbon/LoKI

[9] Jimenez-Redondo, M. et al., Plasma Sources Sci. Technol. 29, 085023 (2020)

*This work was funded by FCT - Fundação para a Ciência e a Tecnologia under projects UIDB/50010/2020, UIDP/50010/2020, LA/P/0061/2020, and 2022.04128.PTDC.

Presenters

  • Shubham Singh Baghel

    • Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Portugal

Authors

  • Shubham Singh Baghel

    • Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Portugal

  • Pedro Pereira

    • Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Portugal

  • Armando Gonçalves

    • Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Portugal

  • Maik Budde

    • LPP, CNRS, École Polytechnique, Sorbonne Université
    • LPP, CNRS, École Polytechnique, Sorbonne Université, Université Paris-Saclay, IP-Paris, Palaiseau, France

  • Jean-Paul Booth

    • LPP, Ecole Polytechnique, Sorbonne Université, Institut Polytechnique de Paris, CNRS, France

  • Olivier Guaitella

    • LPP, Ecole Polytechnique, CNRS, France
    • LPP, Ecole Polytechnique, Sorbonne Université, Institut Polytechnique de Paris, CNRS, France
    • LPP, Ecole Polytechnique, CNRS

  • Luis Marques

    • Centro de Física das Universidades do Minho e do Porto, Universidade do Minho, Braga, Portugal

  • Nuno Pinhão

    • Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Portugal

  • Carlos Pintassilgo

    • Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa 1049-001, Lisboa, Portugal

  • Luís L Alves

    • Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Portugal