Tailoring of Structural and Optical Properties of Electrosprayed β-Ga2O3 Nanostructures via Self- Assembly

The present article demonstrates the fabrication of various β-Gallium Oxide (Ga2O3) nanostructures (NSs) by low-cost and scalable electrospraying (ES) methods via self-assembly (SA). The effect of the annealing sequences on the self-assembled β-Ga2O3 NSs has been detailed. The comparative studies of NSs and nanoflakes (NFs) growth with annealing effect at different stages of self-assembly time (SAT) have been explored further. The fabricated NSs and NFs have been investigated using x-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The comparative study of categorized growth samples shows better crystalline quality when moving from the category 1 (C1) sample to the category 3 (C3) sample. The annealing sequences with SAT play a significant role in crystal formation and its quality, optical properties, and morphology of the Ga2O3 NSs. The optical properties of NSs have been derived from the normal incidence of absorbance measurements. The maximum observed energy band gap is ~5.40 eV. Traps and impurities play a critical role in the formation and deformation of energy bands in crystals. The photoluminescence (PL) spectra further reveal the variation in the intensity of luminescence of different emission bands due to the variation in the number of defect states and impurities in the NSs.