Field emission properties of nano-structured cobalt ferrite (CoFe2O4) synthesized by low-temperature chemical method

Abstract

We report on the field-emission properties of structure-morphology controlled nano-CoFe2O4 (CFO) synthesized via a simple and low-temperature chemical method. Structural analyses indicate that the spongy-CFO (approximately, 2.96 nm) is nano-structured, spherical, uniformly-distributed, cubic-structured and porous. Field emission studies reveal that CFO exhibit low turn-on field (4.27 V/mu m) and high emission current-density (775 mu A/cm(2)) at a lower applied electric field of 6.80 V/mu m. In addition, extremely good emission current stability is obtained at a pre-set value of 1 mu A and high emission spot-density over large area (2 x 2 cm(2)) suggesting the applicability of these materials for practical applications in vacuum micro-/nano-electronics.