Interferometric optical fiber sensor with a polyoxometalate-doped xerogel for the detection of ammonia and VOCs

This study presents the development and evaluation of an interferometric optical fiber sensor (I-OFS) based on a Single Mode Fiber-No Core Fiber-Single Mode Fiber (SMF-NCF-SMF) structure and functionalized with a silica xerogel doped with a titanium (IV)-containing polyoxomolybdate (GeMoTi). The sen...

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Detalles Bibliográficos
Autores: Hernández López, Claudia, Rosales Reina, María Beatriz, Reinoso, Santiago, Garrido Segovia, Julián José, López Torres, Diego, Elosúa Aguado, César
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Universidad Pública de Navarra
Repositorio:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/56071
Acceso en línea:https://hdl.handle.net/2454/56071
Access Level:acceso abierto
Palabra clave:Ammonia
Interferometric structure
Polyoxometalate (POM)
Volatile Organic Compounds (VOCs)
Xerogel
Descripción
Sumario:This study presents the development and evaluation of an interferometric optical fiber sensor (I-OFS) based on a Single Mode Fiber-No Core Fiber-Single Mode Fiber (SMF-NCF-SMF) structure and functionalized with a silica xerogel doped with a titanium (IV)-containing polyoxomolybdate (GeMoTi). The sensor behavior was tested under saturated atmospheres of ammonia, water, and various volatile organic compounds (VOCs), including methylamine, ethanol, acetone, and toluene. The response was characterized in terms of wavelength shifts, which are highlightable for ammonia and methylamine due to their strong chemical interactions with the doped xerogel. The response and recovery times were evaluated for each analyte, pointing out ammonia as the compound with the fastest response time and most stable detection performance, while methylamine exhibited longer recovery due to stronger binding. Calibrations with ammonia concentrations from 56 to 313 ppmm demonstrated linearity (R² = 0.98), low hysteresis (6%) and repeatability. These results support the hypothesis of using GeMoTi-doped xerogels to enhance the response of I-OFSs toward ammonia and related amines.