Field emission investigations of solvothermal synthesized and soaked rutile-TiO₂ nanostructures

In present work we report synthesis of rutile-TiO₂ by using a simple solvothermal method. The formation of pure single phase rutile-TiO₂ has been confirmed by X-ray diffraction (XRD) and Raman spectroscopy analysis. The XRD analysis revealed that as-prepared and soaked-TiO₂ has pure rutile phase with tetragonal crystal structure. The field emission scanning electron microscopy and high resolution transmission electron microscopy analysis shows that as-prepared TiO₂ has nano-rods like morphology whereas soaked-TiO₂ has nano-flowers like morphology with atomically sharp edges. The UV–Visible spectroscopy analysis showed that as-prepared and soaked rutile-TiO₂ nano-structures have absorption edge in the visible range and having band gap of ~ 3.58 eV. The field emission (FE) properties of as-prepared and soaked rutile-TiO₂ nano-structures were investigated and it was observed that as-prepared and soaked rutile-TiO₂ display excellent FE properties with low turn-on field (~ 4.8 V/µm for 10 µA/cm²), maximum current density [~ 444 µA/cm² (as-prepared) and 508 µA/cm² (soaked)] and superior current stability (~ 3 h for ~ 1 µA). The obtained results show that the rutile-TiO₂ nanostructures can be useful for practical applications in vacuum nano/microelectronic devices.