Structural, Morphological, and Optical Properties of Ag‐Doped TiO₂ Thin‐Film over Fiber Optic Substrate for Sensing Applications

Abstract

Ag‐doped TiO2 (rAg/Ti, r 1−3 = 2, 4, 6 wt%) is synthesized by a hydrothermal technique. Different characterizations, that is, X‐ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) analysis, photoluminescence (PL) spectra analysis, X‐ray photoelectron spectroscopy (XPS), field emission scanning electron microscope (FESEM), energy dispersive X‐ray analysis (EDX), and Brunauer–Emmett–Teller (BET) analysis, are conducted to study the utility of the developed thin‐film material as a sensing medium over the fiber substrate. The as‐prepared material is hydrothermally deposited over the optical fiber to construct a fiber optic sensing probe. The optical properties of TiO2 are simulated theoretically by MATLAB simulation that reveals that optical absorption appears at the wavelength of 763 nm. The initial performance of the rAg/Ti‐based optical fiber is investigated with the amine group in the range of 500−1500 ppm and a satisfactory response is found toward ethylenediamine (EDA) analytes with average sensitivity (S av, in %) as 41.81 at 1200 ppm.

Photocatalytic CO2 Reduction Using an Amorphous TiO2-Encapsulated Cs2AgBiBr6 Nanocrystal: Selective Methane Formation

“…The peaks at 436 and 417 cm –1 observed in Cs 2 AgBiBr 6 –aTiO 2 NC in the inset of Figure a indicate the vibration of the Ti–O–Ti bond as a result of amorphous TiO 2 matrix formation around the Cs 2 AgBiBr 6 NC . The prominent bond at 1400 cm –1 in the nanocomposite indicates the vibration of the Ti entity in the Ti–O–Ag bond, which is evident from the XPS results, as discussed earlier . The peaks for surface-adsorbed water (H–O–H) and hydroxyl group (O–H) are represented by bonds at 3325 and 1625 cm –1 , respectively.…”

“…To further confirm the titania coating for forming aTiO 2wrapped Cs 2 AgBiBr 6 NCs, FTIR spectroscopy is performed on 49 The prominent bond at 1400 cm −1 in the nanocomposite indicates the vibration of the Ti entity in the Ti−O−Ag bond, which is evident from the XPS results, as discussed earlier. 50 The peaks for surface-adsorbed water (H−O−H) and hydroxyl group (O−H) are represented by bonds at 3325 and 1625 cm −1 , respectively.…”

Ag‐Doped Free‐Standing 2D TiO2 Sheets: Electronic, Optical, Magnetic, and Self‐Healing Behaviour

“…Interestingly, oxygen deficit and Ti interstitials alter electronic character of the sheets and therefore controlled doping without inducing defects is challenging. [42][43][44] An optical band gap of 2D-TiO 2 below 2 eV is apt for various promising electronic/optoelectronic/excitonic applications, however, it has not experimentally been achieved yet.…”

“…Owing to doping‐tunable optical transparency and electrical conductivity, 2D Ag‐doped TiO 2 (2D ATO) is a promising candidate for flexible electronic/optoelectronic device applications. Interestingly, oxygen deficit and Ti interstitials alter electronic character of the sheets and therefore controlled doping without inducing defects is challenging [42–44] . An optical band gap of 2D‐TiO 2 below 2 eV is apt for various promising electronic/optoelectronic/excitonic applications, however, it has not experimentally been achieved yet.…”