Single-molecule precursor-based approaches to cobalt sulphide nanostructures

Area of Science:

• Inorganic Chemistry
• Materials Science
• Nanotechnology

Background:

• Cobalt sulfide nanoparticles have diverse applications.
• Developing controlled synthesis methods for specific cobalt sulfide phases is crucial.
• Single-molecule precursors offer precise control over nanoparticle formation.

Purpose of the Study:

• To synthesize and characterize novel cobalt complexes as single-molecule precursors.
• To prepare cobalt sulfide nanoparticles using these precursors via thermolysis.
• To investigate the phase and morphology of the resulting nanoparticles.

Main Methods:

• Synthesis and characterization of cobalt complexes.
• Thermolysis of cobalt complexes in amine surfactants (hexadecylamine, octadecylamine, oleylamine).
• Powder X-ray diffraction (PXRD) and Transmission Electron Microscopy (TEM) for characterization.

Main Results:

• Successful synthesis of two cobalt complexes: [Co{N(SCNMe(2))(2)}(3)] (1) and [Co{N(SOCN(i)Pr(2))(2)}(2)] (2).
• Thermolysis yielded hexagonal Co(1-x)S from complex 1 and mixed cubic/hexagonal Co(4)S(3) from complex 2.
• Nanoparticles from complex 1 were 10-15 nm spheres/trigons. Complex 2 produced spheres, rods, and faceted crystallites.
• This marks the first observation of the Co(4)S(3) phase in a nanodispersed form.

Conclusions:

• The synthesized cobalt complexes are effective single-molecule precursors for cobalt sulfide nanoparticles.
• The choice of precursor influences the phase and morphology of the resulting cobalt sulfide nanoparticles.
• The study presents a novel route to nanodispersed Co(4)S(3).