{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T16:01:17Z","timestamp":1790006477906,"version":"4.0.1"},"reference-count":52,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Small"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>\n                    Electrochemical nitrate reduction (NO\n                    <jats:sub>3<\/jats:sub>\n                    RR) offers a low\u2010carbon, infrastructure\u2010light route to ammonia (NH\n                    <jats:sub>3<\/jats:sub>\n                    ), but is limited by the kinetically demanding nitrate adsorption\/activation step and an insufficient supply of active hydrogen (\n                    <jats:sup>*<\/jats:sup>\n                    H) to in situ generated N\u2010containing intermediates. Conventional tandem catalysts address this through multi\u2010metal alloying or hetero\u2010elemental coupling to spatially decouple sequential steps. Here we show that an analogous dual functionality emerges within a single\u2010element iron system via potential\u2010induced modulation of the Fe oxidation state, which drives in situ reconstruction of \u03b2\u2010FeOOH into an intrinsic Fe\/Fe\n                    <jats:sub>x<\/jats:sub>\n                    O\n                    <jats:sub>y<\/jats:sub>\n                    Janus interface with spatially distinct catalytic sites. The Fe\n                    <jats:sub>x<\/jats:sub>\n                    O\n                    <jats:sub>y<\/jats:sub>\n                    center promotes NO\n                    <jats:sub>3<\/jats:sub>\n                    <jats:sup>\u2212<\/jats:sup>\n                    adsorption and dynamically participates in a reversible Fe\n                    <jats:sup>2+<\/jats:sup>\n                    \/Fe\n                    <jats:sup>3+<\/jats:sup>\n                    redox cycle with NO\n                    <jats:sub>3<\/jats:sub>\n                    <jats:sup>\u2212<\/jats:sup>\n                    , accelerating the initial nitrate\u2010to\u2010nitrite activation, while the metallic Fe site facilitates water dissociation to continuously supply\n                    <jats:sup>*<\/jats:sup>\n                    H. The Fe\/Fe\n                    <jats:sub>x<\/jats:sub>\n                    O\n                    <jats:sub>y<\/jats:sub>\n                    electrocatalyst delivered an ammonia yield rate of 15\u00a0mg\u00a0cm\n                    <jats:sup>\u22122<\/jats:sup>\n                    h\n                    <jats:sup>\u22121<\/jats:sup>\n                    (17.6\u00a0mmol h\n                    <jats:sup>\u22121<\/jats:sup>\n                    \u00a0mg cat.\n                    <jats:sup>\u22121<\/jats:sup>\n                    ) with an average Faradaic efficiency of 96% and stable performance over extended operation. Spectroscopic analysis and theoretical calculations elucidate the underlying mechanism. This work strengthens the potential of iron\u2010based electrocatalysts and offers a redox\u2010state\u2010driven design principle for constructing tandem catalytic sites in sustainable energy applications.\n                  <\/jats:p>","DOI":"10.1002\/smll.75879","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T15:11:29Z","timestamp":1790003489000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["In Situ Derived Fe\/Fe\n                    <sub>x<\/sub>\n                    O\n                    <sub>y<\/sub>\n                    Janus Electrocatalyst for Efficient Nitrate\u2010to\u2010Ammonia Conversion via Intensifying Nitrate Affinity and Active Hydrogen Supply"],"prefix":"10.1002","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8602-2187","authenticated-orcid":false,"given":"Sourav","family":"Chaule","sequence":"first","affiliation":[{"name":"Department of Civil Urban Earth and Environmental Engineering (CUEEn) UNIST  Ulsan South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rohit","family":"Anand","sequence":"additional","affiliation":[{"name":"Department of Chemistry UNIST  Ulsan South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyun\u2010Woo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Civil Urban Earth and Environmental Engineering (CUEEn) UNIST  Ulsan South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-8171-350X","authenticated-orcid":false,"given":"Kwangyeol","family":"Baek","sequence":"additional","affiliation":[{"name":"Department of Civil Urban Earth and Environmental Engineering (CUEEn) UNIST  Ulsan South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6929-5359","authenticated-orcid":false,"given":"Kwang S.","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry UNIST  Ulsan South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8663-4201","authenticated-orcid":false,"given":"Kwiyong","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Civil Urban Earth and Environmental Engineering (CUEEn) UNIST  Ulsan South Korea"},{"name":"Graduate School of Carbon Neutrality UNIST  Ulsan South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41586\u2010019\u20101001\u20101"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsenergylett.2c01615"},{"key":"e_1_2_8_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.joule.2020.04.004"},{"key":"e_1_2_8_5_1","doi-asserted-by":"publisher","DOI":"10.1002\/cssc.202402031"},{"key":"e_1_2_8_6_1","doi-asserted-by":"publisher","DOI":"10.1039\/d5gc01690h"},{"key":"e_1_2_8_7_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010022\u201029926\u2010w"},{"key":"e_1_2_8_8_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.joule.2019.10.006"},{"key":"e_1_2_8_9_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41929\u2010020\u201000527\u20104"},{"key":"e_1_2_8_10_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41565\u2010022\u201001121\u20104"},{"key":"e_1_2_8_11_1","doi-asserted-by":"crossref","first-page":"3717","DOI":"10.1038\/s41467-025-59052-2","article-title":"Multivariate Covalent Organic Frameworks With Tailored Electrostatic Potential Promote Nitrate Electroreduction to Ammonia in Acid","volume":"16","author":"Cheng Q.","year":"2025","journal-title":"Nature Communications"},{"key":"e_1_2_8_12_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010017\u201001410\u2010w"},{"key":"e_1_2_8_13_1","doi-asserted-by":"publisher","DOI":"10.1038\/nature15743"},{"key":"e_1_2_8_14_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010023\u201036318\u20101"},{"key":"e_1_2_8_15_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202218717"},{"key":"e_1_2_8_16_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202422585"},{"key":"e_1_2_8_17_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010022\u201035664\u2010w"},{"key":"e_1_2_8_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/adfm.202315324"},{"key":"e_1_2_8_19_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.checat.2023.100786"},{"key":"e_1_2_8_20_1","doi-asserted-by":"publisher","DOI":"10.1002\/adma.202407889"},{"key":"e_1_2_8_21_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.joule.2020.12.025"},{"key":"e_1_2_8_22_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202202556"},{"key":"e_1_2_8_23_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010025\u201063923\u2010z"},{"key":"e_1_2_8_24_1","doi-asserted-by":"publisher","DOI":"10.1002\/elan.200302790"},{"key":"e_1_2_8_25_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.apcatb.2021.120844"},{"key":"e_1_2_8_26_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010022\u201035533\u20106"},{"key":"e_1_2_8_27_1","doi-asserted-by":"publisher","DOI":"10.1002\/adma.202402160"},{"key":"e_1_2_8_28_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsomega.9b03550"},{"key":"e_1_2_8_29_1","doi-asserted-by":"publisher","DOI":"10.1002\/celc.202300516"},{"key":"e_1_2_8_30_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsmaterialslett.4c00390"},{"key":"e_1_2_8_31_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.apcata.2024.119650"},{"key":"e_1_2_8_32_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.apcatb.2022.121346"},{"key":"e_1_2_8_33_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.nanolett.5c03072"},{"key":"e_1_2_8_34_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsnano.4c17163"},{"key":"e_1_2_8_35_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010025\u201063317\u20101"},{"key":"e_1_2_8_36_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsmaterialslett.4c00700"},{"key":"e_1_2_8_37_1","doi-asserted-by":"publisher","DOI":"10.1002\/adfm.202514967"},{"key":"e_1_2_8_38_1","doi-asserted-by":"publisher","DOI":"10.1039\/d2ee03461a"},{"key":"e_1_2_8_39_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202300054"},{"key":"e_1_2_8_40_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsami.2c00436"},{"key":"e_1_2_8_41_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41929\u2010023\u201000951\u20102"},{"key":"e_1_2_8_42_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cej.2024.148857"},{"key":"e_1_2_8_43_1","doi-asserted-by":"publisher","DOI":"10.1002\/anie.202415300"},{"key":"e_1_2_8_44_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.cej.2024.149560"},{"key":"e_1_2_8_45_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.nanoen.2023.108543"},{"key":"e_1_2_8_46_1","doi-asserted-by":"publisher","DOI":"10.1038\/srep23183"},{"key":"e_1_2_8_47_1","doi-asserted-by":"publisher","DOI":"10.1021\/acs.est.2c02663"},{"key":"e_1_2_8_48_1","doi-asserted-by":"publisher","DOI":"10.1002\/smll.202509440"},{"key":"e_1_2_8_49_1","doi-asserted-by":"publisher","DOI":"10.1002\/adma.202304508"},{"key":"e_1_2_8_50_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.apcatb.2024.124528"},{"key":"e_1_2_8_51_1","doi-asserted-by":"publisher","DOI":"10.1021\/jacs.3c10516"},{"key":"e_1_2_8_52_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.electacta.2008.03.048"},{"key":"e_1_2_8_53_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsenergylett.0c02082"}],"container-title":["Small"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/smll.75879","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/smll.75879","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/smll.75879","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T15:11:31Z","timestamp":1790003491000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/smll.75879"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9,21]]},"references-count":52,"alternative-id":["10.1002\/smll.75879"],"URL":"https:\/\/doi.org\/10.1002\/smll.75879","archive":["Portico"],"relation":{},"ISSN":["1613-6810","1613-6829"],"issn-type":[{"value":"1613-6810","type":"print"},{"value":"1613-6829","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9,21]]},"assertion":[{"value":"2026-06-08","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-15","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-09-21","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e75879"}}