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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">najo</journal-id><journal-title-group><journal-title xml:lang="en">Nanosystems: Physics, Chemistry, Mathematics</journal-title><trans-title-group xml:lang="ru"><trans-title>Наносистемы: физика, химия, математика</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2220-8054</issn><issn pub-type="epub">2305-7971</issn><publisher><publisher-name>Университет ИТМО</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.17586/2220-8054-2022-13-4-445-455</article-id><article-id custom-type="elpub" pub-id-type="custom">najo-255</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Статьи</subject></subj-group></article-categories><title-group><article-title>Near-IR photoluminescence and structural properties of TiO2 powders with nanocrystalline anatase/brookite matrix</article-title><trans-title-group xml:lang="ru"><trans-title></trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0922-3863</contrib-id><name-alternatives><name name-style="western" xml:lang="en"><surname>Ulyanova</surname><given-names>E. S.</given-names></name></name-alternatives><email xlink:type="simple">tsivileva.yekaterina@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8617-3329</contrib-id><name-alternatives><name name-style="western" xml:lang="en"><surname>Shalaeva</surname><given-names>E. V.</given-names></name></name-alternatives><email xlink:type="simple">shalaeva@ihim.uran.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5643-966X</contrib-id><name-alternatives><name name-style="western" xml:lang="en"><surname>Ponosov</surname><given-names>Yu. S.</given-names></name></name-alternatives><email xlink:type="simple">ponosov@imp.uran.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3685-5337</contrib-id><name-alternatives><name name-style="western" xml:lang="en"><surname>Lipina</surname><given-names>O. A.</given-names></name></name-alternatives><email xlink:type="simple">lipinaolgaa@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2454-8674</contrib-id><name-alternatives><name name-style="western" xml:lang="en"><surname>Markov</surname><given-names>A. A.</given-names></name></name-alternatives><email xlink:type="simple">aamarkov1@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff xml:lang="en" id="aff-1"><institution>Institute of Solid State Chemistry of Ural Branch of the Russian Academy of Sciences</institution><country>Russian Federation</country></aff><aff xml:lang="en" id="aff-2"><institution>M. N. Mikheev Institute of Metal Physics of Ural Branch of the Russian Academy of Sciences</institution><country>Russian Federation</country></aff><pub-date pub-type="collection"><year>2022</year></pub-date><pub-date pub-type="epub"><day>06</day><month>06</month><year>2025</year></pub-date><volume>13</volume><issue>4</issue><fpage>445</fpage><lpage>455</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Ulyanova E.S., Shalaeva E.V., Ponosov Y.S., Lipina O.A., Markov A.A., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Ulyanova E.S., Shalaeva E.V., Ponosov Y.S., Lipina O.A., Markov A.A.</copyright-holder><copyright-holder xml:lang="en">Ulyanova E.S., Shalaeva E.V., Ponosov Y.S., Lipina O.A., Markov A.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://nanojournal.ifmo.ru/jour/article/view/255">https://nanojournal.ifmo.ru/jour/article/view/255</self-uri><abstract><p>The properties are studied for near-IR photoluminescence (PL) observed at 865 - 870 nm for precipitated TiO2 powders having nanocrystalline anatase/brookite structure: the dependence of NIR PL on annealing in oxygen, on content and crystallinity quality of brookite, and on excitation energy (Eex). NIR PL in bi-phase powders was found to demonstrate a behavior characteristic of NIR PL in brookite. NIR emission intensity grows with increasing brookite content and at annealing in oxygen, when oxygen vacancies content decreases and crystallinity quality of brookite improves. The results indicate that in the bi-phase powders, brookite contains deep-level defect traps which are regarded responsible for NIR-PL in brookite and are favorable for photocatalytic reactions. NIR emission is observed for the band (Eex ~ Eb) and below band-gap green (Eex &lt; Eb) excitation. A mechanism underlying NIR-PL in brookite with green excitation is suggested to be similar to that for the red PL known for anatase at below band-gap excitation.</p></abstract><kwd-group xml:lang="en"><kwd>anatase/brookite TiO2</kwd><kwd>nano-powders</kwd><kwd>NIR-photoluminescence</kwd><kwd>structural properties</kwd><kwd>defect states</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Katal R., Masudy-Panah S., et al. A review on the synthesis of the various types of anatase TiO2 facets and their applications for photocatalysis. Chemical Engin. J., 2020, 384, 123384.</mixed-citation><mixed-citation xml:lang="en">Katal R., Masudy-Panah S., et al. A review on the synthesis of the various types of anatase TiO2 facets and their applications for photocatalysis. Chemical Engin. 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