{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:08:15Z","timestamp":1792789695211,"version":"4.5.0"},"reference-count":31,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T00:00:00Z","timestamp":1790380800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Science Foundation of Henan","award":["252300420961"],"award-info":[{"award-number":["252300420961"]}]},{"name":"Natural Science Foundation of Henan","award":["262300420696"],"award-info":[{"award-number":["262300420696"]}]},{"name":"Science and Technology Project of Henan Province","award":["252102210193"],"award-info":[{"award-number":["252102210193"]}]},{"name":"Henan Institute of Technology Doctoral Research Fund Project","award":["9001KQ2424"],"award-info":[{"award-number":["9001KQ2424"]}],"id":[{"id":"https:\/\/ror.org\/024f5m737","id-type":"ROR","asserted-by":"crossref"}]},{"award":["9001KQ2424"],"award-info":[{"award-number":["9001KQ2424"]}],"id":[{"id":"https:\/\/ror.org\/024f5m737","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Henan Key Laboratory of Advanced Cable Materials and Intelligent Manufacturing","award":["CAMIM2025008"],"award-info":[{"award-number":["CAMIM2025008"]}]},{"name":"Key Scientific Research Project of Higher Education Institutions in Henan Province","award":["25B510018"],"award-info":[{"award-number":["25B510018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Interface engineering of the electron transport layer (ETL) is an effective strategy for enhancing the performance and stability of all-inorganic perovskite solar cells (PSCs). Herein, Na+-intercalated vermiculite nanosheets were introduced as a low-cost natural interfacial modifier for the TiO2 ETL in CsPbI2Br PSCs. The nanosheets were prepared via an aqueous-phase exfoliation process and deposited onto the TiO2 surface to regulate the buried TiO2\/CsPbI2Br interface. Morphological and spectroscopic characterizations revealed that vermiculite modification reduced the surface roughness of TiO2, altered its surface chemical\/electronic environment and was associated with improved interfacial energy-level alignment. As a result, the quality of the CsPbI2Br film was significantly improved, leading to larger grains, enhanced crystallinity, a lower apparent trap-state density, and more efficient interfacial charge-transfer behavior. Electrical characterizations further confirmed enhanced charge extraction, reduced carrier recombination, and an increased built-in potential in the modified devices. Consequently, the vermiculite-modified devices exhibited simultaneous improvements in power conversion efficiency (PCE), open-circuit voltage, and short-circuit current density, with the best-performing device reaching a PCE of 13.94%. In addition, the modified device retained 84.51% of its initial PCE after storage in air for 35 days, significantly higher than the 71.1% retained by the control device. These findings highlight the potential of Na+-intercalated vermiculite nanosheets as low-cost natural modifiers for TiO2\/CsPbI2Br buried-interface engineering in efficient and stable all-inorganic PSCs.<\/jats:p>","DOI":"10.3390\/nano16191216","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T08:18:46Z","timestamp":1790583526000},"page":"1216","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Na+-Intercalated Two-Dimensional Vermiculite-Modified TiO2 Electron Transport Layer for Enhanced CsPbI2Br Perovskite Solar Cells"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6709-2099","authenticated-orcid":false,"given":"Yuan","family":"Xu","sequence":"first","affiliation":[{"name":"Xinxiang Engineering Research Center for Advanced Energy Storage Batteries and Materials, School of Materials Science and Engineering, Henan Institute of Technology, 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