The first joint publication by Geo-Astro

A unique case was experimentally investigated - the purely thermal reaction CO2 + 2NH3 → NH4+NH2COO- in the presence of a porous dust layer separating the reactants CO2 and NH3. Thus, the diffusion of the reactants through (along the pores of) the dust layer was inevitable for the reaction to proceed. The experiments showed that the presence of the dust layer was a requirement for the reaction to occur. This result clearly argues for (i) efficient diffusion of molecules on/in cosmic dust, (ii) an underestimated role of surface catalysis in cosmic dust astrochemistry, and (iii) potentially efficient dust-promoted chemistry in warm cosmic environments, such as protostellar envelopes and protoplanetary discs. In many cases, solid reactants on astrophysical dust grains may not be mixed at high concentrations or in the required ratios; diffusion across the dust surface would then be a requirement for the development of pathways to complexity in space.

Potapov A., Pollok K., Langenhorst F., McCoustra M., Garrod R., "Cosmic dust as a prerequisite for the formation of complex organic molecules in space?", The Astrophysical Journal, 2025, 993, 49, DOI : https://doi.org/10.3847/1538-4357/ae08aeExternal link