Enhanced room temperature gas sensing performance of iron-doped titanium dioxide nanocomposite

In this study, TiO₂ nanoparticles and iron-doped (1%, 3%, and 5%) TiO₂ nanocomposites were synthesized using the hydrothermal technique. XRD pattern confirmed that the pure TiO₂ has an anatase phase with a tetragonal structure. The average crystallite sizes of the Fe-doped (1%, 3%, and 5%) TiO₂ nanocomposites (FT1, FT3, and FT5) were calculated from 9 nm to 13 nm. The metal oxides corresponding to TiO₂ were identified using Fourier-transform infrared spectroscopy. The emission peak observed at 647 nm (red emission) in the photoluminescence spectrum was due to oxygen vacancies. The band gap value of pure and iron-doped (optimized) TiO₂ was found to be 3.46 and 3.57 eV using the Kubelka Munk method. FE-SEM and HRTEM images revealed agglomerated particles with cubic shapes. The magnetic properties of the samples were soft and ferromagnetic. The N₂ adsorption-desorption isotherms revealed that a remarkably high specific surface area of the FT3 sample was 550.56 m² g^− 1 with a pore size of 3 nm. Fe-doped TiO₂ nanocomposites possess high gas-sensing activity towards acetone with low response and recovery times, and good sensitivity.