Details

Autor(en) / Beteiligte

• Islam, Shumaila

Titel

Fast responsive anatase nanoparticles coated fiber optic pH sensor

Ist Teil von

• Journal of alloys and compounds, 2021-01, Vol.850, p.156246, Article 156246

Ort / Verlag

Lausanne: Elsevier B.V

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The sol-gel method is employed to synthesize the phenol red encapsulated anatase nanoparticles (PR/ANPs) matrix at low temperature (60 °C). Field emission scanning electron microscopy/Energy Dispersive X-Ray (FESEM/EDX) analysis shows porous nanostructures, and uniform elemental distribution. Atomic Force Microscopy exhibited that after phenol red (PR) encapsulation, average surface roughness (Ra) is increased up to ∼ 20 nm than pure anatase matrix Ra ∼14 nm. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy analysis confirmed the presence of bond ∼ 1054 cm−1 which is indicative of good PR encapsulation within the anatase matrix. X-ray diffraction analysis (XRD) shows intense peak corresponding to phenol along with anatase peaks suggested the interaction of Ti and O atoms with PR species. High resolution transmission electron micrographs (HR-TEM) analysis exhibited crystalline anatase structure before and after encapsulation along (101) direction. The average particle size is observed 5 nm for ANPs matrix which reduced to 3 nm after encapsulation. Observed high surface area 218 m2/g after encapsulation is helpful to enhance the activity of the sensing device. Thermogravimetric analysis (TGA) shows that after 422 °C, no mass weight loss is observed which confirmed the thermal stability of synthesized matrices. After encapsulation, observed low refractive index 1.8 at 550 nm indicates the porous nature of the matrix. The fiber optic pH sensor shows a linear response over the dynamic pH range 1–12, sensitivity is calculated as 1.83 counts/pH at 454 nm with determination coefficient (R2) ∼ 0.97. The proposed sensing device has fast response time 1.09s–0.42s within acidic-basic media, good reversibility, and validity. Experimental findings suggested that synthesized material has great potential in photonic devices/applications. [Display omitted] •Low-temperature sol-gel method is employed to synthesize the Phenol red encapsulated anatase nanoparticles matrix.•Average surface roughness 20 nm and 137 nm thickness is observed by microscopic analysis.•High specific surface area 218 m2/g after encapsulation is helpful to enhance the activity of the sensing device.•Fiber optic pH sensor shows a linear response, sensitivity 1.83 counts/pH at 454 nm with R2 ∼ 0.97.•The sensing device has fast response time 1.09s-0.42s within acidic-basic media, good reversibility, and validity.