Fabrication of nanostructured lead-free bismuth sodium titanatethin film and its liquefied petroleum gas sensing

• Published in: Sensors and actuators. A. Physical. 2020-01, Vol.301, p.111765, Article 111765
• Main Authors: Singh, Monika, Yadav, B.C., Kumar, Utkarsh, Ranjan, Ashok, Srivastava, Richa, Kaur, Manmeet
• Format: Article
• Language: English
• Subjects: Bismuth; Bismuth sodium titanate; Crystallites; Detection; Diffusion; Ferroelectric; Fourier transforms; Gas sensors; Gravimetric analysis; Infrared analysis; Infrared spectrophotometers; Lead free; Liquefied petroleum gas; LPG; LPG gas sensor; Macroporous; Nanostructured materials; Optical properties; Porosity; Raman spectroscopy; Recovery time; Response time; Room temperature; Sodium titanate; Sol-gel processes; Spectroscopic analysis; Spin coating; Surface structure; Thermal analysis; Thin films
• ISSN: 0924-4247; 1873-3069
• DOI: 10.1016/j.sna.2019.111765

[Display omitted] •The minimum crystallite size of BNT was found as 9 nm and avg. size was found as 15 nm.•The pores on the film surface have sizes in the range 100 nm–500 nm and average pore size calculated as 350 nm.•Fringe spacing as d(hkl) = 2.3666 Å from HRTEM and Raman absorption bands appear at 275 cm−1, 526 cm−1, 583 cm−1 and 800 cm−1.•UV-vis spectroscopy gave the optical band gap as 5.4 eV, FTIR bands at 629 cm−1 confirm the formation of perovskite.•Maximum sensitivity for LPG as 2.158, response time as 22 s and recovery time as 26 s for 0.25 vol.%. In the present paper, a study on bismuth sodium titanate thin film based liquefied petroleum gas sensing was carried out. The thin film of synthesized material has been prepared by using sol-gel spin coating technique and was characterized by various techniques such as XRD, TGA, SEM, TEM, EDS, UV-Spectroscopy, Raman and FTIR. XRD analysis confirms the formation of bismuth sodium titanate (BNT) with a minimum crystallite size of 9 nm. SEM images show the microporous surface structure of the film. Optical characterization of the film was carried out by UV–vis spectrophotometer; Fourier transforms infrared spectroscopy and Raman spectroscopy. Thermal analysis graph of BNT precursor via Thermal Gravimetric process was studied. LPG sensing of bismuth sodium titanate was done at room temperature below LEL. Maximum sensitivity was found as 2.158 at 3 vol% and minimum response time of 22 s and recovery time 26 s for 0.25 vol% of LPG.