Realization of Efficient Field Emitter Based on Reduced Graphene Oxide‐Bi₂S₃ Heterostructures

Abstract

Herein, Bi 2 S 3 nanorods and reduced graphene oxide (rGO)‐Bi 2 S 3 heterostructures are synthesized using a simple hydrothermal method. The structural, morphological, chemical, and elemental analysis of as‐synthesized materials is performed using X‐ray diffraction (XRD), Raman spectroscopy, field‐emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X‐ray photoelectron spectroscopy (XPS). Field emission (FE) studies are carried out on both pristine Bi 2 S 3 nanorods and rGO‐Bi 2 S 3 heterostructure samples at a base pressure of ≈1 × 10 −8 mbar. The results show that the rGO‐Bi 2 S 3 heterostructure emitter has superior FE performance compared to pristine Bi 2 S 3 emitters in terms of the turn‐on field (2.6 V μm −1 at 10 μA cm −2 ) and threshold field (4.0 V μm −1 at 100 μA cm −2 ) along with a high emission current density of ≈1464 μA cm −2 at an applied electric field of 7.0 V μm −1 . The rGO‐Bi 2 S 3 heterostructure emitter exhibits very good emission current stability, tested for more than 3 h duration, characterized by standard deviation values ≈2.84 and 4.06, corresponding to preset values 12 and 100 μA. This study implies that one‐step hydrothermal route can be efficiently used to synthesize organic–inorganic heterostructures that possess unique morphology. Furthermore, the synthesized rGO‐Bi 2 S 3 heterostructure emitter shows potential as an electron source for practical application in vacuum microelectronic devices.