One-Pot Synthesis of Cobalt Selenide Nanoparticles

Abstract

ABSTRACT Cobalt selenide nanoparticles were synthesized via a simple one-pot reaction between cobalt chloride and sodium selenide. Sodium selenide was prepared by using sodium formaldehyde sulfoxylate (SFS) in high boiling solvents such as N,N′-diemthylformamide (DMF) or ethylene glycol (EG). SFS acts as a reducing agent to selenium as well as a surfactant to the nanoparticles and enables control of particle nucleation and growth during synthesis. Black powders so obtained were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), and infrared (IR) spectroscopy. The broad XRD pattern indicated an orthorhombic structure with particle diameter of about 20 nm and TEM showed deshaped spherical particles of similar dimensions. XPS confirmed oxidized surfaces because the Se 3d binding energy spectrum showed two peaks indicating the formation of selenium dioxide on the surface.