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Upconversion Nanoparticles as Luminescent Probes for Cement

  • Safety is a key parameter for the design and construction of buildings. The most widely used construction material to date is concrete that consists of about 15-20 wt.-% cement, which is responsible for the main concrete properties, i.e., strength and durability. Despite many standards regulating the quality of cement, at present, there exists no viable method to track the cement life cycle “from cradle to grave”. This led to an increasing interest in simple and robust methods for studying the processes and changes occurring during the life cycle of cement. In this context, we explored the applicability of fluorescence measurements which can be performed with relatively inexpensive and miniaturized instrumentation yet require robust optical probes which survive the harsh cement environment. Therefore, we developed a platform of lanthanide-based upconversion nanoparticles (UCNPs), consisting of a NaYF4 matrix doped with Yb3+ and Er3+ with sizes between 20 nm and 55 nm, which showSafety is a key parameter for the design and construction of buildings. The most widely used construction material to date is concrete that consists of about 15-20 wt.-% cement, which is responsible for the main concrete properties, i.e., strength and durability. Despite many standards regulating the quality of cement, at present, there exists no viable method to track the cement life cycle “from cradle to grave”. This led to an increasing interest in simple and robust methods for studying the processes and changes occurring during the life cycle of cement. In this context, we explored the applicability of fluorescence measurements which can be performed with relatively inexpensive and miniaturized instrumentation yet require robust optical probes which survive the harsh cement environment. Therefore, we developed a platform of lanthanide-based upconversion nanoparticles (UCNPs), consisting of a NaYF4 matrix doped with Yb3+ and Er3+ with sizes between 20 nm and 55 nm, which show characteristic multi-color emission patterns, composed of narrow bands of varying intensity in the ultraviolet, visible, near-infrared, and short-wave spectral region and examined their potential for cement probing and the non-invasive monitoring of the hydration processes occurring during cement formation. UCNPs of different size and chemical composition were synthesized via a thermal decomposition approach under inert conditions. The tailor-made design of different emission patterns was achieved by tuning particle size and morphology, material composition, and particle surface chemistry in upscaleable syntheses. For cement probing, different types of UCNPs were added to cement and the evolution of the UCNP emission pattern was used to probe in-situ changes of physico-chemical parameters in the cementitious environment during hydration, utilizing a simple and portable custom-designed optical setup. The observed changes in the UCNP emission patterns are characteristic for a given particle size, surface chemistry, and cement composition. In addition to fluorescence measurements, conventional isothermal heat flow calorimetry was used to study the influence of UCNP addition on cement hydration kinetics. Subsequently, both sets of measurements were correlated. Our results underline the potential of our optical approach ad UCNPs for the non-invasive probing of cementitious systems and cement hydration. This can be also exploited for cutting-edge applications of construction materials such as 3D concrete printing.zeige mehrzeige weniger

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Autor*innen:Philipp Kossatz
Koautor*innen:Alexander Mezhov, Elina Andresen, Wolfram Schmidt, Carsten Prinz, Ute Resch-Genger
Dokumenttyp:Posterpräsentation
Veröffentlichungsform:Präsentation
Sprache:Englisch
Jahr der Erstveröffentlichung:2023
Organisationseinheit der BAM:1 Analytische Chemie; Referenzmaterialien
1 Analytische Chemie; Referenzmaterialien / 1.2 Biophotonik
6 Materialchemie
6 Materialchemie / 6.3 Strukturanalytik
7 Bauwerkssicherheit
7 Bauwerkssicherheit / 7.4 Baustofftechnologie
DDC-Klassifikation:Naturwissenschaften und Mathematik / Chemie / Analytische Chemie
Freie Schlagwörter:Cement Hydration; Fluorescence Spectroscopy; Upconversion
Themenfelder/Aktivitätsfelder der BAM:Chemie und Prozesstechnik
Veranstaltung:Summer School Exciting Nanostructures
Veranstaltungsort:Bad Honnef, Germany
Beginndatum der Veranstaltung:31.07.2023
Verfügbarkeit des Dokuments:Datei im Netzwerk der BAM verfügbar ("Closed Access")
Datum der Freischaltung:12.09.2023
Referierte Publikation:Nein
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