Metal catalysis in astrophysical environments Victoria Cabedo 1 , Martin McCoustra 1 , J. Llorca 2 , J.M. Trigo-Rodriguez 3 , A. Rimola 4 1 ICS-Heriot Watt University, UK, 2 Universitat Politecnica de Catalunya, Spain, 3 ICE-CSIC/ IEEC, Spain, 4 Universitat Autonoma de Barcelona, Spain The evolution of simple compounds into the complex organic molecules (COMs) that ultimately gave rise to life is still a matter of debate. The transformation of simple molecules in the gas phase is difficult in typical astrophysical environments where temperatures and densities are very low and radiation fluxes may be high. Consequently, it is widely accepted that the formation of COMs occurs on the surface of dust grains, which are present in all the stages of evolution of a planetary system. Those grains can act as a third bodies, absorbing excess energy from reactions, and are also covered in ices (mainly made of water, CO, N 2 and other simple organics such as methanol) which act to concentrate reactants and increase the chances of reactive collisions. However, dust grains are also rich in metallic components, such as Fe and Ni, which are well known on Earth to act as catalysts for the formation of organic compounds in processes such as the Fischer-Tropsch (FT) to produce hydrocarbons, and the Haber-Bosch (HB) for the synthesis of ammonia. While, this type of chemistry is still poorly studied and unaccounted for on astrophysical chemical models, some studies have already point to the catalytic activity of the metallic inclusions and their potential role in the chemical evolution of different astrophysical environments [1-4]. In this talk, we will discuss the results published in [5], where we investigated the potential catalytic activity of meteoritic materials towards FT synthesis, achieving the synthesis of small hydrocarbons and alcohols. Additionally, we will introduce our new project on astrocatalysis, where we plan to investigate in greater detail the catalytic processes that could occur in different astrophysical environments for different metallic compositions of the dust grains. We will create different catalytic systems that are representative of space weathering processes, and exposing them to different mixtures of gas, including carriers of sulfur and phosphorous, under different local environmental conditions (stellar nebula, protoplanetary disks and protoplanets), to observe the reactivity and the chemical evolution. References 1. J. Llorca and I. Casanova. Formation of carbides and hydrocarbons in chondritic interplanetary dust particles: A laboratory study. , 33(2):243–251, Mar. 1998. doi: 10.1111/j.1945-5100.1998.tb01629.x 2. J. Llorca and I. Casanova. Reaction between H2, CO, and H2S over Fe,Ni metal in the solar nebula: Experimental evidence for the formation of sulfur- bearing organic molecules and sulfides. , 35(4):841–848, July 2000. doi: 10.1111/j.1945- 5100.2000.tb01467.x. 3. R. F. Ferrante, M. H. Moore, J. A. Nuth, and T. Smith. NOTE: Laboratory Studies of Catalysis of CO to Organics on Grain Analogs. , 145(1):297–300, May 2000. doi: 10.1006/icar.2000.6350. 4. W. C. Tucker, A. H. Quadery, A. Schulte, R. G. Blair, W. E. Kaden, P. K. Schelling, and D. T. Britt. Strong catalytic activity of iron nanoparti- cles on the surfaces of reduced olivine. , 299:502–512, Jan. 2018. doi:1016/j.icarus.2017.08.027. 5. V. Cabedo, J. Llorca, J. M. Trigo-Rodriguez, and A. Rimola. Study of Fischer- Tropsch-type reactions on chondritic meteorites. , 650:A160, June 2021. doi: 10.1051/0004-6361/202039991.
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