Synthesis, Optical, and Structural Studies of Iron Sulphide Nanoparticles and Iron Sulphide Hydroxyethyl Cellulose Nanocomposites from Bis-(Dithiocarbamato)Iron(II) Single-Source Precursors.

Athandwe M Paca,Peter A Ajibade

doi:10.3390/nano8040187

Abstract

In this study, Fe(II) complexes of phenyldithiocarbamate, dimethyldithiocarbamate and imidazolyldithiocarbamate were used as single-source precursors to prepare iron sulphide nanoparticles by thermolysis in oleic acid/octadecylamine (ODA) at 180 °C. The nanoparticles were dispersed into hydroxyethyl cellulose (HEC) to prepare iron sulphide/HEC nanocomposites. Ultraviolet-Visible (UV-Vis), Photoluminescence (PL), Fourier Transform Infrared (FTIR), powder X-ray diffraction (pXRD), high-resolution transmission electron microscopy (HRTEM), Field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDS) were used to characterize the iron sulphide nanoparticles and corresponding HEC nanocomposites. The absorption spectra studies revealed that the nanoparticles were blue shifted due to quantum confinement and the optical band gaps of the nanoparticles are 4.85 eV for FeS1, 4.36 eV for FeS2, and 4.77 eV for FeS3. The emission maxima are red-shifted and broader for the nanoparticles prepared from phenyldithiocarbamate. Rod-like and spherically shaped iron sulphide particles were observed from the HRTEM images. The crystallite sizes from the HRTEM images are 23.90–38.89 nm for FeS1, 4.50–10.50 nm for FeS2, and 6.05–6.19 nm for FeS3 iron sulphide nanoparticles, respectively. pXRD diffraction patterns confirmed that FeS1 is in the pyrrhotite-4M crystalline phase, FeS2 is in the pyrrhotite phase, and FeS3 is in the troilite phase of iron sulphide. The phases of the iron sulphide nanoparticles indicate that the nature of the precursor complex affects the obtained crystalline phase. FTIR spectra studies confirmed the incorporation of the nanoparticles in the HEC matrix by the slight shift of the O–H and C–O bonds and the intense peaks on the nanoparticles. FESEM images of the iron sulphide nanoparticles showed flake-like or leaf-like morphologies with some hollow spheres. The EDS confirmed the formation of iron sulphide nanoparticles by showing the peaks of Fe and S.

Highlights

In recent years, metallic nanoparticles have received tremendous research attention because of their unique physical, chemical and biological properties associated with their broad surface-to-volume ratio and due to quantum confinement effects [1,2,3,4,5,6]
There is a need to develop single source precursors from metal ion that are biocompatible such as iron [24,26,27,28]— the current study focuses on the use of iron(II) dithiocarbamate complexes as precursors for the preparation of iron sulphide nanoparticles
We present the optical and structural studies of iron sulphide nanoparticles in three different crystalline phases prepared from three bis-(dithiocarbamato)iron(II) complexes single-source precursors

Summary

Introduction

Metallic nanoparticles have received tremendous research attention because of their unique physical, chemical and biological properties associated with their broad surface-to-volume ratio and due to quantum confinement effects [1,2,3,4,5,6]. The single-source precursor (SSP) approach has become a versatile and effective route for the preparation of metal sulphide nanoparticles [12,13,14,15] This approach allows controlled growth of nanocrystals with excellent optical properties [16]. There is a need to develop single source precursors from metal ion that are biocompatible such as iron [24,26,27,28]— the current study focuses on the use of iron(II) dithiocarbamate complexes as precursors for the preparation of iron sulphide nanoparticles. We present the optical and structural studies of iron sulphide nanoparticles in three different crystalline phases prepared from three bis-(dithiocarbamato)iron(II) complexes single-source precursors. The optical and structural properties of the iron sulphide nanoparticles/HEC nanocomposites were studied using Ultraviolet-Visible (UV-Vis), Photoluminescence (PL), powder X-ray diffraction (pXRD) high-resolution transmission electron microscopy (HRTEM), Field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), and Fourier Transform Infrared Spectroscopy (FTIR)

Materials and Reagents

Preparation of Iron Sulphide Nanoparticles

Characterization Techniques

Results and Discussion