{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T05:19:47Z","timestamp":1788326387359,"version":"build-2803163510"},"reference-count":30,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,30]],"date-time":"2026-08-30T00:00:00Z","timestamp":1788048000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100014188","name":"Ministry of Science and ICT","doi-asserted-by":"publisher","award":["RS-2025-02315174-2026"],"award-info":[{"award-number":["RS-2025-02315174-2026"]}],"id":[{"id":"10.13039\/501100014188","id-type":"DOI","asserted-by":"publisher"}]},{"award":["RS-2025-02315174-2026"],"award-info":[{"award-number":["RS-2025-02315174-2026"]}],"id":[{"id":"https:\/\/ror.org\/01wpjm123","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Seoul Metropolitan Government","award":["2026-ANCHOR-01-007-04"],"award-info":[{"award-number":["2026-ANCHOR-01-007-04"]}]},{"award":["2026-ANCHOR-01-007-04"],"award-info":[{"award-number":["2026-ANCHOR-01-007-04"]}],"id":[{"id":"https:\/\/ror.org\/002wfgr58","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Ministry of Education"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>Two-dimensional (2D) organic\u2013inorganic hybrid perovskites exhibit coupled ionic, electronic, and electromechanical responses that can strongly influence local charge transport. Here, solution-processed mixed-halide butylammonium lead perovskite crystals were mechanically exfoliated and investigated using X-ray diffraction, atomic force microscopy, piezoresponse force microscopy (PFM), and conductive atomic force microscopy (c-AFM). PFM measurements under \u22125, 0, and +5 V revealed clear bias-dependent changes in amplitude and phase, indicating an electric field-sensitive local electromechanical response. Local c-AFM measurements showed nonlinear bipolar hysteresis, with a pronounced increase in current near +7\u20138 V and a decrease near \u22127 to \u22126 V during the subsequent negative sweep. Because the crystals are mixed ionic\u2013electronic conductors and the nanoscale tip\u2013sample junction introduces substantial injection and contact barriers, the observed behavior is interpreted as resistive switching-like conductivity modulation, rather than definitive ferroelectric switching. The results are consistent with the combined contributions of charge injection, trap filling, possible ionic redistribution, and piezoelectricity-associated modulation of the local transport barrier. These findings provide nanoscale insight into electric field-dependent electromechanical and out-of-plane conductive behaviors in layered 2D hybrid perovskites.<\/jats:p>","DOI":"10.3390\/ijms27177770","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T09:48:36Z","timestamp":1788256116000},"page":"7770","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Nanoscale Electromechanical and Conductive Properties of a Layered Two-Dimensional Hybrid Perovskite"],"prefix":"10.3390","volume":"27","author":[{"given":"Hee-Chang","family":"Jeon","sequence":"first","affiliation":[{"name":"Department of Mechanical, Robotics and Energy Engineering, Dongguk University, Jung-gu, Seoul 04620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-4861-2687","authenticated-orcid":false,"given":"Woohyuk","family":"Jang","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Robotics and Energy Engineering, Dongguk University, Jung-gu, Seoul 04620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-8146-5567","authenticated-orcid":false,"given":"Jiseon","family":"Yun","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Robotics and Energy Engineering, Dongguk University, Jung-gu, Seoul 04620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"given":"Sein","family":"Min","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Robotics and Energy Engineering, Dongguk University, Jung-gu, Seoul 04620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3223-7523","authenticated-orcid":false,"given":"Joong Yeon","family":"Lim","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Robotics and Energy Engineering, Dongguk University, Jung-gu, Seoul 04620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0783-6997","authenticated-orcid":false,"given":"Young-Seong","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Robotics and Energy Engineering, Dongguk University, Jung-gu, Seoul 04620, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2230","DOI":"10.1021\/acs.chemrev.0c01006","article-title":"The 2D Halide Perovskite Rulebook: How the Spacer Influences Everything from the Structure to Optoelectronic Device Efficiency","volume":"121","author":"Li","year":"2021","journal-title":"Chem. 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A"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/17\/7770\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T04:29:57Z","timestamp":1788323397000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/27\/17\/7770"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,30]]},"references-count":30,"journal-issue":{"issue":"17","published-online":{"date-parts":[[2026,9]]}},"alternative-id":["ijms27177770"],"URL":"https:\/\/doi.org\/10.3390\/ijms27177770","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,8,30]]}}}