{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T15:43:49Z","timestamp":1792683829172,"version":"4.5.0"},"reference-count":50,"publisher":"American Chemical Society (ACS)","license":[{"start":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T00:00:00Z","timestamp":1792540800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-029"},{"start":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T00:00:00Z","timestamp":1792540800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-037"},{"start":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T00:00:00Z","timestamp":1792540800000},"content-version":"stm-asf","delay-in-days":0,"URL":"https:\/\/doi.org\/10.15223\/policy-045"}],"funder":[{"DOI":"10.13039\/100000082","name":"Division of Graduate Education","doi-asserted-by":"publisher","award":["2139319"],"award-info":[{"award-number":["2139319"]}],"id":[{"id":"10.13039\/100000082","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100015350","name":"Institute for Energy Efficiency, University of California, Santa Barbara","doi-asserted-by":"publisher","award":["NA"],"award-info":[{"award-number":["NA"]}],"id":[{"id":"10.13039\/100015350","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Nonoxidative methane conversion offers a promising route for the coproduction of hydrogen and value-added hydrocarbons without CO2 emissions. Among emerging approaches, pulsed plasmas can provide potential advantages by enabling high energy deposition, rapid quenching, and generation of active nonthermal species. This work systematically investigates how pulsed energy deposition from nanosecond-to-millisecond time scales (10 to 50 mJ\/pulse) influences methane plasma characteristics (electron density and gas temperature), reaction mechanisms, conversion, and energy efficiency. Nanosecond discharges produced the highest overall C2 selectivity (&amp;gt;70%), with up to 20% for C2H4; in this regime, methane dissociation proceeded through both electron-impact and thermal dissociation, whereas longer pulses were predominantly thermal. Pulsed plasma conversion was similar to thermal arcs (\u223c377 kJ\/mol CH4) and specific energy requirements to produce C2H2 and H2 were 15 kWh\/kg and 40 kWh\/kg, respectively, in 100 \u03bcs long discharges. The product distribution was largely determined by thermal processes involving dehydrogenation reactions (Kassel\u2019s reaction scheme). High gas temperatures preferentially favored C2H2 formation over C2H4, and C2H4 selectivity decreased with increasing pulse width. Overall, these results demonstrate that pulse width and energy can be used to tailor hydrocarbon selectivity and can help design pulsed plasma systems for efficient production of value-added hydrocarbons and hydrogen.<\/jats:p>","DOI":"10.1021\/jacs.6c13735","type":"journal-article","created":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T07:01:26Z","timestamp":1792566086000},"source":"Crossref","is-referenced-by-count":0,"title":["Energy Deposition Timescale\nControls Chemistry in\nPulsed Methane Plasmas"],"prefix":"10.1021","author":[{"given":"Norleakvisoth","family":"Lim","sequence":"first","affiliation":[{"name":"University of California , , , ,","place":["Santa Barbara, California, United States, 93106"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0123-9649","authenticated-orcid":true,"given":"Michael J.","family":"Gordon","sequence":"additional","affiliation":[{"name":"University of California , , , ,","place":["Santa Barbara, California, United States, 93106"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,10,21]]},"reference":[{"issue":"32","key":"2026102211093436800_cit1","doi-asserted-by":"publisher","first-page":"11855","DOI":"10.1021\/acs.iecr.1c01679","article-title":"Methane Pyrolysis for Zero-Emission\nHydrogen Production: A Potential Bridge Technology from Fossil Fuels\nto a Renewable and Sustainable Hydrogen Economy","volume":"60","author":"Sa\u0301nchez-Bastardo","year":"2021","journal-title":"Ind. 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