CO2 detection using In and Ti doped SnO2 nanostructures: Comparative analysis of gas sensing properties.

This research explores the gas-sensing characteristics of undoped SnO 2 , as well as indium (In:SnO 2) and titanium (Ti:SnO 2) doped SnO 2 nanostructures, which were synthesized using a homogeneous precipitation technique. Structural analyses indicate the presence of a tetragonal rutile phase with a preferred orientation along the (110) plane, with both doped samples showing shifts towards higher angles. Raman spectroscopy confirms the vibrational modes associated with SnO 2 in both the pure and In: SnO 2 samples, while the Ti: SnO 2 sample reveals vibrational modes corresponding to both SnO 2 and TiO 2. Fourier-transform infrared (FTIR) spectroscopy indicates shifts in the O-Sn-O and Sn-O bonds in the doped samples, suggesting the effects of doping. X-ray photoelectron spectroscopy (XPS) results imply a combination of SnO and SnO 2 phases in the undoped SnO 2 , while In: SnO 2 samples display In-O bonding and the presence of metallic indium, and Ti: SnO 2 shows Ti-O bonding. Scanning electron microscopy (SEM) images show agglomerated particles in the pure and In-doped samples, whereas the Ti-doped samples exhibit a flake-like structure. Transmission electron microscopy (TEM) analysis verifies the integration of dopants into the SnO 2 crystal lattice, with average crystallite sizes measured at 44.46 nm for undoped, 34.06 nm for In: SnO 2 , and 42.63 nm for Ti: SnO 2. Gas-sensing experiments for CO 2 detection reveal that In: SnO 2 demonstrates the most significant sensing response. These results underscore the impact of doping on the structural, morphological, and gas-sensing attributes of SnO 2 nanostructures, offering important insights for the advancement of efficient carbon dioxide sensors. [ABSTRACT FROM AUTHOR]