Abstract Owing to the fiber optic sensing applications, the cavity shaped cresol red (CR) immobilized anatase nanoparticles (CR-ANPs) are synthesized by sol-gel route. The homogeneous distribution of CR species within ANPs is confirmed by EDX mapping analysis. The chemical bonding between Ti and functional groups indicated the successful immobilization of CR species in the anatase matrix. Thermally stable CR-ANPs have average surface roughness ∼ 9 nm, a large surface area of 210 m2/g, small pore volume 0.12 cm3/g, and crystallite size 4 nm. The sensing response of the proposed device is found to be 7.05 counts/pH within pH 1-7 at 453 nm with the determination coefficient (R2) ∼ 0.95. Whereas, in basic media (pH 9-12), the sensor response is found to be 5.95 counts/pH. Experimental findings suggested that this proposed material is of pronounced interest because it can be used within extreme acidic and basic media without any deterioration/leaching.

中文翻译：

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基于热和光学功能化锐钛矿纳米腔的光纤 pH 传感器

摘要 由于光纤传感的应用，通过溶胶-凝胶途径合成了空腔形甲酚红（CR）固定化锐钛矿纳米粒子（CR-ANPs）。EDX 映射分析证实了 ANP 内 CR 物种的均匀分布。Ti 和官能团之间的化学键表明 CR 物质在锐钛矿基质中的成功固定。热稳定的 CR-ANPs 具有平均表面粗糙度 ∼ 9 nm、210 m2/g 的大表面积、0.12 cm3/g 的小孔体积和 4 nm 的微晶尺寸。发现所提出的装置的传感响应为 7.05 计数/pH，在 453 nm 处的 pH 值 1-7 内，决定系数 (R2) 约为 0.95。而在碱性介质 (pH 9-12) 中，发现传感器响应为 5.95 计数/pH。