{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T12:35:41Z","timestamp":1793277341944,"version":"4.5.0"},"reference-count":74,"publisher":"Wiley","issue":"10","license":[{"start":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T00:00:00Z","timestamp":1779235200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,5,20]],"date-time":"2026-05-20T00:00:00Z","timestamp":1779235200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/100000001","name":"NSF","doi-asserted-by":"publisher","award":["CBET\u20102453450"],"award-info":[{"award-number":["CBET\u20102453450"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["chemistry-europe.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["ChemSusChem"],"published-print":{"date-parts":[[2026,5,27]]},"abstract":"<jats:p>\n                    N\u2010heterocyclic aromatics can reversibly store H\n                    <jats:sub>2<\/jats:sub>\n                    in chemical bonds through (de)hydrogenation reactions at\u2009&lt;473\u2009K, but their reaction pathways remain incompletely understood. Here, we perform (de)hydrogenation reactions of (methyl)indoles over a Pd\/Al\n                    <jats:sub>2<\/jats:sub>\n                    O\n                    <jats:sub>3<\/jats:sub>\n                    catalyst, combined with density functional theory (DFT) calculations of adsorbate binding on Pd surfaces. Hydrogenation proceeds through 2,3\u2010dihydroindole intermediates that further hydrogenate to 8H\u2010indoles. Hydrogenation occurs first at the pyrrole ring rather than the benzene ring, likely due to differences in resonance stability. In contrast, dehydrogenation of 8H\u2010indoles proceeds via initial dehydrogenation of the pyrrolidine ring, showing that the pyrrole ring is more reactive than the benzene ring in both reaction directions. (Methyl)indole adsorption free energies on Pd(111) weaken with the degree of hydrogenation but are broadly similar regardless of methyl group position. Dehydrogenation of 8H\u2010indoles forms 6H\u2010imine and\/or 4,5,6,7\u2010tetrahydro intermediates which further dehydrogenate to indoles. Initial hydrogenation of indole rings yields predominantly\n                    <jats:italic>cis<\/jats:italic>\n                    \u20108H\u2010indoles (\n                    <jats:italic>cis\/trans<\/jats:italic>\n                    \u2009&gt;\u200910), reflecting kinetically controlled syn\u2010facial H atom addition to planar\u2010bound indoles. At longer times, 8H\u2010indole\n                    <jats:italic>cis\/trans<\/jats:italic>\n                    ratios decay toward equilibrium values (\n                    <jats:italic>cis\/trans \u223c<\/jats:italic>\n                    2\u20133). In 8H\u2010indole dehydrogenation,\n                    <jats:italic>cis\/trans<\/jats:italic>\n                    isomerization occurs in parallel with forward dehydrogenation steps. This work provides mechanistic insights into the (de)hydrogenation of N\u2010heterocyclic H\n                    <jats:sub>2<\/jats:sub>\n                    carriers over supported Pd catalysts.\n                  <\/jats:p>","DOI":"10.1002\/cssc.70720","type":"journal-article","created":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T04:23:19Z","timestamp":1779337399000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Reaction Pathways in the (De)hydrogenation of N\u2010Heterocyclic Liquid Hydrogen Carriers Over Supported Pd Catalysts"],"prefix":"10.1002","volume":"19","author":[{"given":"Matthew D.","family":"Edgar","sequence":"first","affiliation":[{"name":"Department of Chemical and Biological Engineering University of Wisconsin\u2010Madison  Madison Wisconsin 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