Electric field emission in GdNiO3 microflower

GdNiO3 microflowers were synthesized by hydrothermal method with unit sizes of about 2.2-3.5 mu m and petal sizes of similar to 75-100 nm. The X-ray diffraction pattern (XRD) and Raman spectra reveal an orthorhombic crystal structure with the space group Pbnm and various Raman active vibrational modes i.e., A(g), B-1 (g), B-2 (g) associated with rare earth nickelates. The total density of states (TDOS) was calculated by density functional theory (DFT) study using a hybrid functional (HSE06) and the volume of TDOS near the Fermi level confirms the semiconducting nature of GdNiO3 with band gap similar to 0.688 eV. The local bulk work function (phi) was estimated theoretically at similar to 5.35 eV from DFT calculations which is one of the essential parameters for the field enhancement factor (beta). Field emission current density (J) vs. applied electric field (E) divulges a low turn-on field (E-to)similar to 4.6 V/mu m@1 mu A/cm(2) and a threshold field (E-th)similar to 5.2 V/mu m@10 mu A/cm(2) respectively. The FowlerNordheim (F-N) model was introduced to calculate beta -1637 and long-term field emission current stability was observed experimentally > 4 h at the preset values of current 2 mu A and 10 mu A, respectively. The easy preparedness, low turn-on field, and long-term current stability without significant decay suggest this material to be an efficient electron field emitting material in the rare-earth nickelates series.