Photo responsive transport properties of hydrothermally synthesized SnO2 layered nanoflakes/Au Schottky junction

Abstract

Stannic oxide (SnO2) nano-materials has been drawing attentions for applications in transparent electrodes, hazardous-gas sensors, electron transport layers in thin-film solar cells, microelectronics, etc. In this present report, we have analyzed the junction characteristics of the hydrothermally synthesized SnO2 layered nano-flakes (LNFs). The two-dimensional flake like structure of the SnO2 samples was verified from the scanning electron microscopy (SEM) micrographs with a mean thickness of 11.70 nm. The chemical composition of the LNFs was found to be 1:3.51 (Sn:O), from the energy dispersive x-ray spectroscopy (EDS) study. The UV–Vis absorption analysis validates the quantum confinement effect from the widening (blue shifting) of the bandgap to 3.75 eV. The junction characteristics of the indium tin oxide (ITO)/ SnO2 LNFs/gold (Au) device depict the Schottky type properties with barrier potentials, 0.85 eV and 0.63 eV in dark and illumination conditions respectively. However, in both conditions, the ideality factor remains unaltered (0.93). The light induced diminution of the barrier potential and confinement induced widening of band gap make the LNFs suitable for photo-sensors and solar cells.