Journal of Sol-Gel Science and Technology https://doi.org/10.1007/s10971-018-4894-5 ORIGINAL PAPER: FUNCTIONAL COATINGS, THIN FILMS AND MEMBRANES (INCLUDING DEPOSITION TECHNIQUES) Effect of molar concentration on physical properties of spraydeposited SnO 2 thin films using nebulizer S. Palanichamy 1 ● J. Raj Mohamed 2 ● K. Deva Arun Kumar 3 ● M. Anitha 1 ● S. Pandiarajan 4 ● L. Amalraj 1 Received: 8 October 2018 / Accepted: 23 November 2018 © Springer Science+Business Media, LLC, part of Springer Nature 2018 Abstract In the present paper, tin dioxide (SnO 2 ) thin films had been fabricated with different precursor concentration in the range of 0.01–0.09 M onto amorphous glass substrates utilizing nebulizer spray method. The effect of precursor concentration on electrical, morphological, structural, optical, and photoluminescence properties has been investigated. XRD spectrum revealed that the polycrystalline nature of SnO 2 thin films with tetragonal structure in the range of precursor concentration 0.03–0.09 M, which are having a favorable growth orientation along (110) direction. The estimated average crystallite size varied between 22 and 53 nm. UV-Visible spectrum exposes the transmittance of SnO 2 thin films lies between 90 and 78% in the visible range. The direct band gap energy reduced from 3.83 to 3.71 eV on increasing precursor concentration upto 0.07 M and then it was further increased. Photoluminescence spectra at room temperature exhibited a strong peak at 362 nm with shoulder peak at 376 nm and two broad peaks are 493 nm and 518 nm. SEM analysis illustrated that the polyhedron-like grains were homogeneously arranged over the film surface. The film prepared at 0.07 M precursor concentration shows the least resistivity 2.41 × 10 -3 Ω-cm and good figure of merit 16.41 × 10 -3 (Ω/sq) -1 . Graphical Abstract Highlights ● SnO 2 thin films were deposited with different precursor concentration (0.01–0.09 M) using nebulized spray pyrolysis (NSP) technique. ● Crystallite size in the range of 22–53 nm. ● Transmittance decreased from 90 to 78% in the visible region. ● Minimum electrical resistivity 2.41 × 10 -3 Ω-cm obtained at 0.07 M precursor concentration. ● Highest figure of merit is found to be 16.41 × 10 -3 (Ω/sq) -1 . * L. Amalraj amalraj57@yahoo.co.in 1 Research Department of Physics, V.H.N.S.N. College, Virudhunagar, Tamilnadu 626001, India 2 Research Department of Physics, H.H. The Rajah’s College, Pudukkottai, Tamilnadu 622001, India 3 Department of Physics, Arul Anandar College, Karumathur, Tamilnadu 625514, India 4 Department of Physics, Devanga Arts College, Aruppukottai, Tamilnadu 626101, India 1234567890();,: 1234567890();,: