Chemical Vapor Deposition of β-HgS Nanoparticles From a Precursor, bis(cinnamylpiperazinedithiocarbamato) Mercury(II)

Abstract

Chemical vapor deposition method for the synthesis of β-HgS (meta cinnabar) nanoparticles is reported with bis(cinnamylpiperazinedithiocarbamato)mercury(II) as the single source precursor. Crystalline structure, size, morphology and composition of the products are characterized by X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) analysis. PXRD shows (111), (220), (200), (311), (222), (400), (331), (420) reflections characteristic of β-HgS nanoparticles. SEM micrographs display the spherical nature of the b-HgS nanoparticles. EDX analysis showed the presence of Hg and S.HRTEM images confirm the spherical nature of the nanoparticles with their size in the range of 5–10 nm. The results are in agreement with those estimated from the XRD pattern. XPS signals observed at 162.6, 162.8, 222.3, 99.9, and 104.1 eV are due to S_{2p (3/2}, _1/2), S_{2s (1/2)}, and Hg_{4f (7/2, 5/2)} respectively. The precursor [Hg (cpzdtc)₂] was synthesized and characterized by IR and NMR (¹H and ¹³C). Single crystal X-ray crystallography of precursor shows the presence of HgS4 distorted tetrahedral coordination environment, with a distinct Hg–S bond asymmetry.

Keywords:

• dithiocarbamate
• thioureide
• precursor
• chemical vapor deposition
• powder diffraction
• transmission electron microscope
• semiconductor nanoparticles