Browsing by Author "Revaprasadu, Neerish"
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Item Bis(piperidinedithiocarbamato)pyridinecadmium(II) as a Single-Source Precursor for the Synthesis of CdS Nanoparticles and Aerosol-Assisted Chemical Vapour Deposition (AACVD) of CdS thin films(2014) Lewis, David J.; Revaprasadu, Neerish; Mlowe, Sixberth; Malik, Azad; Mubofu, Egid B.; O'Brien, Paul; Raftery, JamesThe synthesis and single-crystal X-ray structure of bis(piperidinedithiocarbamato)pyridinecadmium(II), [Cd(S2C(NC5H10))2(NC5H5)] are reported and its use as a precursor for the synthesis of hexagonal CdS nanoparticles and CdS thin films is presented. Thermogravimetric analysis (TGA) of this complex showed clean decomposition in two steps to give CdS. Thermolysis of the complex in hexadecylamine at different temperatures in the range 190 ¬ 270 °C gave CdS nanostructures including nanorods and oval shaped particles. The band gap of the as-synthesized CdS nanoparticles varied as the temperature was increased. CdS thin films with optical direct band gaps of ca. 2.4 eV were deposited by aerosol-assisted chemical vapour deposition (AACVD) in the temperature range 350 to 450 oC using the same precursor. Powder X-ray diffraction (p-XRD) patterns of CdS nanoparticles and thin films confirmed the hexagonal phase of CdS.Item Cadmium Sulfide Quantum Dots Stabilized By Castor Oil and Ricinoleic Acid(Elsevier, 2016) Kyobe, Joseph W.; Mubofu, Egid B.; Makame, Yahya M. M.; Mlowe, Sixberth; Revaprasadu, NeerishCastor oil and ricinoleic acid (an isolate of castor oil) are environmentally friendly bio-based organic surfactants that have been used as capping agents to prepare nearly spherical cadmium sulfide quantum dots (QDs) at 230, 250 and 280 °C. The prepared quantum dots were characterized by Ultra violet–visible (UV–vis), Photoluminescence (PL), Transmission Electron Microscopy (TEM), High Resolution Transmission Electron Microscopy (HRTEM) and X-ray diffraction (XRD) giving an overall CdS QDs average size of 5.14±0.39 nm. The broad XRD pattern and crystal lattice fringes in the HRTEM images showed a hexagonal phase composition of the CdS QDs. The calculated/estimated average size of the prepared castor oil capped CdS QDs for various techniques were 4.64 nm (TEM), 4.65 nm (EMA), 5.35 nm (UV–vis) and 6.46 nm (XRD). For ricinoleic acid capped CdS QDs, the average sizes were 5.56 nm (TEM), 4.78 nm (EMA), 5.52 nm (UV–vis) and 8.21 nm (XRD). Optical properties of CdS QDs showed a change of band gap energy from its bulk band gap of 2.42–2.82 eV due to quantum size confinement effect for temperature range of 230–280 °C. Similarly, a blue shift was observed in the photoluminescence spectra. Scanning electron microscope (SEM) observations show that the as-synthesized CdS QDs structures are spherical in shape. Fourier transform infra-red (FTIR) studies confirms the formation of castor oil and ricinoleic acid capped CdS QDs.Item Cashew nut shell: a potential bio-resource for the production of bio-sourced chemicals(Green Chemistry, 2019) Mgaya, James; Shombe, Ginena B; Masikane, Siphamandla C; Mlowe, Sixberth; Mubofu, Egid B; Revaprasadu, NeerishExploitation of agricultural waste as green starting materials to produce various valuable products is attracting the attention of academic, industrial and other practitioners. Cashew nut shell (CNS) and its liquid extract (CNSL) in particular have been identified as agro-wastes rich in valuable and functional renewable products. The unique structural features of the CNSL constituents offer the possibility for different modifications to suit various applications. This review article provides recent developments in CNS and CNSL as green sources for use in the production of biorenewable chemicals, materials and energy. Extraction methods and applications of CNS, CNSL and isolates are discussed. Furthermore, a literature survey of the current status and efforts made on the utilization of these agricultural and food wastes for different applications is well outlined.Item Castor Oil Production and Applications(Nova Science Publishers, 2018) Mlowe, Sixberth; Masikane, Siphamandla C; Kyobe, Joseph W; Mubofu, Egid B; Revaprasadu, NeerishCastor oil extracted from the castor oil seeds of Ricinus communis is an important naturally occurring oil identified as a useful raw material for diverse industrial applications. Historically, the oil has been used in medicinal fields (as a laxative agent) as well as in cosmetics. The main attractive attributes of this oil include biodegradability and non-volatility. Thus, this has recently enabled derivatization to afford value-added chemicals through alternative green synthetic protocols. The oil contains a large percentage of an unusual fatty acid, 12-hydroxy-9-cisoctadecenoic acid, commonly known as ricinoleic acid. Ricinoleic acid can be easily extracted through chemical processes and subsequently exploited as a biosource for the production of high-grade lubricants, transparent typewriter and printing inks, textile dyes, leather preservation agents and polyamide nylon-type fibres. The most recent advances identify castor oil and its major isolate (ricinoleic acid) as potential green solvents and/or capping agents in the synthesis of high quality nanomaterials and nanocomposites.Item CdS thin films deposition by AACVD: effect of precursor type, decomposition temperature and solvent.(Journal of Materials Science: Materials in Electronics, 2018-09) Ketchemen, Kevin IY; Mlowe, Sixberth; Nyamen, Linda D; Ndifon, Peter T; O'Brien, Paul; Revaprasadu, NeerishABSTRACT Hexagonal cadmium sulfide (CdS) thin films were deposited on glass substrates by Aerosol Assisted Chemical Vapour Deposition (AACVD) using cadmium(II) dithiocarbamate and xanthate complexes in tetrahydrofuran (THF) and mixed solvents (THF+ chloroform) at 400 and 450 oC. The surface morphology and size of the CdS films determined using scanning electron microscopy (SEM), showed the formation of films of various morphologies depending on the precursor, the deposition temperature and solvent used. An increase in temperature resulted in an increase in particle size and a change in morphology with the formation of CdS films with distorted structures. The CdS films showed an overall blue shift in their absorption band edge (2.35 – 2.49 eV) compared to the bulk CdS. In dithiocarbamates, a slight blue shift was observed with a shift to high wavelengths with the reduction of the carbon chain of the dithiocarbamate and an increase in temperature; while in xanthate, a strong blue shift was observed at both deposition temperatures. The use of mixed THF + chloroform solvent at 450 oC showed the formation of films with irregular structures compared to those deposited using THF solvent alone, indicating the role of the solvent in the shape direction of the films formation. The elemental composition determined by energy dispersive X-ray spectroscopy (EDX) measurements revealed the 1:1 (Cd:S) ratio in all the samples confirming the stoichiometry of the CdS films.Item Cdse Quantum Dots Capped with Naturally Occurring Biobased Oils(2015) Kyobe, Joseph W.; Mubofu, Egid B.; Makirita, Yahya M. M.; Mlowe, Sixberth; Revaprasadu, NeerishWe report a green synthesis of CdSe quantum dots (QDs) using bio-based materials (castor oil and ricinoleic acid) as capping agents. The absorption spectra of the as-synthesized CdSe QDs showed typical features of quantum confinement. The particle sizes of QDs were determined using the absorption band edges and found to be 3.81 to 6.80 nm and 5.91 to 8.31 nm for the entire range of reaction temperatures for QD-capped with castor oil (CSTO) and ricinoleic acid (RA), respectively. The photoluminescence spectra showed narrow emission peaks. The transmission electron microscopy (TEM) images showed spherical particles with sizes comparable to those determined from the absorption spectra. Comparatively, large particles were observed for RA capped CdSe QDs than those stabilized by CSTO. X-ray diffraction patterns revealed that the synthesized CdSe quantum dots have cubic structure. The particle sizes of CdSe deduced from X-ray diffraction measurements were in excellent agreement with those deduced from absorption spectra and TEM images. The d-spacings from the HRTEM images were consistent with those reported in literature. The surface area and the agglomeration number for as-synthesized CdSe QDs of different sizes are also reported.Item Deposition of Bi2S3 thin films from heterocyclic bismuth (III) dithiocarbamato complexes.(Polyhedron, 2018) Kun, Walter N; Mlowe, Sixberth; Nyamen, Linda D; Akerman, Matthew P; O'Brien, Paul; Ndifon, Peter T; Revaprasadu, NeerishTwo heterocyclic dithiocarbamate complexes, tris- (piperidinedithiocarbamato)bismuth(III) (1) and tris-(tetrahydroquinolinedithiocarbamato) bismuth(III) (2) were synthesized and characterized by elemental analysis and thermogravimetric analysis. The structure of complex (1) was confirmed by single-crystal X-ray analysis. Both complexes were used as single source precursors for the deposition of bismuth sulfide thin films by aerosol assisted chemical vapour deposition (AACVD) at 350, 400, 450 °C and spin coating followed by thermal treatment at 350 °C, 400 °C and 450 °C. Both deposition methods, gave sulfur deficient polycrystalline films of bismuthinite. Scanning electron microscopy (SEM) images of the films showed morphology was dependent on the solvent mixture, temperature, precursor type and method of deposition. AACVD gave films with hexagonal nanoplatelets, leaf-like platelet, ribbon-like fibre, needle-like fibre morphologies. Films in the form of rods and interwoven nanowires were obtained from spin coating.Item Functionalized Mesoporous Organo-Silica Nanosorbents for Removal of Chromium (III) Ions from Tanneries Wastewater(Springer Link, 2016) Gervas, Charles; Mubofu, Egid B.; Mdoe, James; Revaprasadu, NeerishOrgano-silica mesoporous materials with cyano functional groups were prepared by a one pot co-condensation of 2-cyanoethyltriethoxysilane (CETS) and tetraethoxysilane (TEOS) at ratios of 1:4 and 1:9 using either sunflower oil or n-dodecylamine as templating agents. The tethered cyano groups were used as adsorption sites or hydrolysed to carboxylic surface functional groups. The prepared materials were characterized by diffuse reflectance infrared Fourier transform spectroscopy, atomic force microscopy (AFM), Brunauer, Emmettt and Teller, thermogravimetric analysis, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Results indicated that materials with cyano and carboxylic surface groups were successfully prepared. AFM results indicated that primary particles with irregular shapes and grain size ranging from 0.28 ± 0.03 to 0.46 ± 0.08 µm were obtained depending on the CETS to TEOS ratio used and the structure directing template. SEM and TEM micrographs depict spherical like morphology of the same size as portrayed by AFM results. Sunflower cyano functionalized micelle template silica (MTS-S-CN) at a ratio of 1:9 had surface area of 760.5 m2/g and average pore diameters of 3.5 nm while MTS-S-CN at a ratio 1:4 had pore diameter of 10.1 nm with surface area of 734.1 m2/g. On the other hand, the MTS-S-COOH (1:9) had surface area of 975.9 m2/g with pore diameter of 4.6 nm whereas MTS-S-COOH (1:4) had surface area of 740.1 m2/g with pore diameter of 6.3 nm. The materials were used in adsorption studies of Cr(III) ions from tannery wastewater. Cr(III) ions removal ranged from 48 to 83 % depending on the adsorbent functional group and the organosilyl groups to silica ratio. This study has indicated that materials prepared were good adsorbents with an adsorption maximum of 19.7 mg Cr(III) ions per g of adsorbent.Item Heterocyclic Dithiocarbamato-Iron (III) Complexes: Single-Source Precursors for Aerosol-Assisted Chemical Vapour Deposition (AACVD) of Iron Sulfide Thin Films(2016) Mlowe, Sixberth; Lewis, David J.; Malik, Mohammad A.; Raftery, James; Mubofu, Egid B.; O'Brien, Paul; Revaprasadu, NeerishThe biomedical potential of flavonoids is normally restricted by their low water solubility. However, little has been reported on their encapsulation into polyamidoamine (PAMAM) dendrimers to improve their biomedical applications. Generation four (G4) PAMAM dendrimer containing ethylenediaminetetraacetic acid core with acrylic acid and ethylenediamine as repeating units was synthesized by divergent approach and used to encapsulate a flavonoid tetramethylscutellarein (TMScu, 1) to study its solubility and in vitro release for potential bioactivity enhancement. The as-synthesized dendrimer and the dendrimer–TMScu complex were characterized by spectroscopic and spectrometric techniques. The encapsulation of 1 into dendrimer was achieved by a co-precipitation method with the encapsulation efficiency of 77.8% ˘ 0.69% and a loading capacity of 6.2% ˘ 0.06%. A phase solubility diagram indicated an increased water solubility of 1 as a function of dendrimer concentration at pH 4.0 and 7.2. In vitro release of 1 from its dendrimer complex indicated high percentage release at pH 4.0. The stability study of the TMScu-dendrimer at 0, 27 and 40 ˝ C showed the formulations to be stable when stored in cool and dark conditions compared to those stored in light and warmer temperatures. Overall, PAMAM dendrimer-G4 is capable of encapsulating 1, increasing its solubility and thus could enhance its bioactivity.Item Heterocyclic lead(II) thioureato complexes as single-source precursors for the aerosol assisted chemical vapour deposition of PbS thin films(Inorganica Chimica Acta, 2018) Ketchemen, Kevin IY; Mlowe, Sixberth; Nyamen, Linda D; Aboud, Ahmed A; Akerman, Matthew P; Ndifon, Peter T; O'Brien, Paul; Revaprasadu, NeerishThe lead N’-benzoylthioureato complexes of N-morpholine (1) and N-pyrrolidine (2) were synthesized and characterized by elemental analysis, Fourier Transform Infra-Red (FT-IR) spectroscopy, proton nuclear magnetic resonance (1H nmr) and thermogravimetric analyses (TGA). The X-ray single crystal structure of complex (1) was determined. The compounds were both used as single source precursors to deposit PbS films on glass substrates at 350, 400 and 450 °C using aerosol assisted chemical vapour deposition (AACVD) The surface morphology of PbS films were determined by scanning electron microscopy (SEM), the crystalline phases established by powder X-ray diffraction (p-XRD) analyses and composition by energy dispersive X-ray spectroscopy (EDX). The particle sizes were found to range between 82 and 85 nm from complex (1) and 70–105 nm for (2) The PbS films were studied by Near Infra-red (NIR) UV–Vis spectroscopy, band gap ranging from 1.46 to 1.55 eV were observed.Item Lead Chalcogenides Stabilized by Anacardic Acid(Elsevier, 2013-04) Mlowe, Sixberth; Nejo, A. A.; Pullabhotla, Rajasekhar; Mubofu, Egid B.; Ngassapa, Faustine; O'Brien, Paul; Revaprasadu, NeerishPbE (E = S, Se and Te) nanoparticles stabilized by anacardic acid in the shape of spheres and cubes have been synthesized employing a simple solution based thermolysis route at moderate reaction temperatures. The route adheres to some of the principles of 'green' chemistry since a naturally occurring capping ligand, anacardic acid, is employed at a relatively low temperature. The lead sources were varied to study their effect on the morphology of the lead chalcogenide particles.Item Lead(II) halide cinnamaldehyde thiosemicarbazone complexes as single source precursors for oleylamine-capped lead sulfide nanoparticles(Journal of Materials Science: Materials in Electronics, 2018) Masikane, Siphamandla C; Mlowe, Sixberth; Gervas, Charles; Revaprasadu, Neerish; Pawar, Amol S; Garje, Shivram SDifferent PbX2 (X = AcO, Cl, Br, I) metal salts were complexed to cinnamaldehyde thiosemicarbazone ligand. The resulting complexes were characterised using Fourier Transform Infrared spectroscopy, 1H and 13C {1H} Nuclear Magnetic Resonance spectroscopy, elemental analysis and thermogravimetric analysis techniques. They were then used as single source precursors for the preparation of lead sulfide (PbS) nanoparticles using the colloidal thermolysis route where oleylamine is used as the passivating agent. Each SSP is thermolysed at reaction temperatures of 190, 230 and 270 °C. Predominantly cubic-shaped PbS nanoparticles were obtained, with an exception of the truncated nanocubes obtained from thermolysis of the SSP prepared from lead bromide. Varying particle sizes are obtained when the halogen is varied, ranging from ca. 50 to 400 nm. The optical absorbance of the PbS nanoparticles in the UV-Vis- NIR range was found to be blue-shifted when compared to bulk PbS.Item Low Temperature Synthesis of Anacardic-Acid-Capped Cadmium Chalcogenide Nanoparticles(Springer Link, 2014-06) Mlowe, Sixberth; Pullabhotla, Rajasekhar; Mubofu, Egid B.; Ngassapa, Faustine; Revaprasadu, NeerishWe report the low temperature synthesis of CdE (E = S, Se and Te) semiconductor nanoparticles capped by anacardic acid, an environmentally benign naturally occurring capping ligand. The cadmium chalcogenide nanoparticles were synthesized by reacting the reduced chalcogen powder with cadmium chloride to form the corresponding bulk material which was then dispersed in tri-n-octylphosphine (TOP) and thermolysed in anacardic acid. The low temperature of the reaction and the use of a naturally occurring oil solvent make this a relatively green synthetic route. The optical properties of the anacardicacid-capped cadmium chalcogenide particles show evidence of quantum confinement. The particles were characterized by X-ray diffraction and electron microscopy techniques.Item Phase pure Ni3S2 and NiS from bis(N′-ethyl-N-piperazinylcarbodithioato-S,S′)–nickel(II) via solvent thermolysis and aerosol assisted chemical vapour deposition.(New Journal of Chemistry, 2018) Gervas, Charles; Mlowe, Sixberth; Akerman, Matthew P; Revaprasadu, NeerishA bis(N′-ethyl-N-piperazinylcarbodithioato-S,S′)–nickel(II) complex was prepared and characterized using infrared spectroscopy, thermogravimetric and elemental analyses. The crystal X-ray structure for bis(N′-ethyl-N-piperazinylcarbodithioato-S,S′)–nickel(II) was determined. The complex was subsequently used as a single source precursor (SSP) for the synthesis of phase pure Ni3S2 and NiS nanoparticles and thin films via hot injection thermolysis and aerosol assisted chemical vapour deposition (AACVD) routes, respectively. For the hot injection thermolysis route, hexadecylamine (HDA) and oleylamine (OLA) were used as capping groups at varying temperatures. Chloroform was used as the solvent in the AACVD experiments. Powder X-ray revealed that the capping group does not change the phase of nanoparticles formed whereas the AACVD technique produced different phases. Variation of temperature did not affect the phase purity of the nanomaterials formed. The morphology of the thin films obtained via AACVD depended largely on the deposition temperature, whereas for the nanoparticles, temperature and the capping group had a significant impact.Item Preparation of Iron Sulfide Nanomaterials from Iron (II) Thiosemicarbazone Complexes and Their Application in Photodegradation of Methylene Blue(Journal of Inorganic and Organometallic Polymers and Materials, 2018-05) Suroshe, Jagruti S; Mlowe, Sixberth; Garje, Shivram S; Revaprasadu, NeerishIron sulfide nanomaterials were prepared by the solvothermal decomposition of two single source precursors i.e. [FeCl2(cinnamtscz)2] (1) (cinnamtscz = cinnamaldehyde thiosemicarbazone) and [FeCl2(benztscz)2] (2) (benztscz = benzaldehyde thiosemicarbazone) at different temperatures of 230 and 300 °C in the presence of oleylamine. Powder X-ray diffractometry shows the formation of the pyrrhotite phase at both reaction temperatures. The solvothermal decomposition of [FeCl2(cinnamtscz)2] and [FeCl2(benztscz)2] at 230 °C produced iron sulfide nanoparticles in the form of spheres. When the temperature was increased to 300 °C, particles in the form of hexagons and nanorods were obtained. Furthermore, the photocatalytic activities of all the four iron sulfide nanomaterials were tested for the degradation of methylene blue under visible light irradiation. Amongst all the materials, nanospheres of iron sulfide obtained by the solvothermal decomposition of [FeCl2(benztscz)2] at 230 °C showed the highest photocatalytic efficiency (88.40%).Item Progress in Green Solvents for the Stabilisation of Nanomaterials: Imidazolium Based Ionic Liquids(IntechOpen., 2018) Tshemese, Zikhona; Masikane, Siphamandla C; Mlowe, Sixberth; Revaprasadu, NeerishFor over a decade, ionic liquids (ILs) have attracted enormous attention from scientists across the globe. The history of these compounds traces back to 1914 where the inception of the first IL with a melting point of 12°C was made. Years later, a progression of the remarkable related compounds have been discovered. Out of many analogous compounds realized from time to time, the imidazolium class of ionic liquid is the most studied because of their air and moisture stability. The physicochemical properties of ILs differ significantly depending on the anionic/cationic species and alkyl chain length. ILs have found application in many scientific fields the most recent being good solvents and stabilizing agents in the nanomaterial synthesis. Studies have showed that ILs not only stabilize as synthesized nanomaterials but also provide environmentally green routes towards nanomaterials engineering.Item Synthesis and Characterization of Castor Oil and Ricinoleic Acid Capped Cds Nanoparticles Using Single Source Precursors(Elsevier, 2015) Shombe, Ginena B.; Mubofu, Egid B.; Mlowe, Sixberth; Revaprasadu, NeerishWe report the synthesis of castor oil and ricinoleic acid capped CdS nanoparticles by the thermolysis of piperidine (1) and tetrahydroquinoline (2) dithiocarbamate complexes of cadmium(II) at temperatures varying from 190. °C to 300. °C. Reaction parameters such as time and temperature were varied to study their effect on the properties and morphology. The optical properties of CdS were typical of particles that displayed quantum confinement effects. X-ray diffraction studies revealed the existence of both cubic and hexagonal phases depending on the reaction conditions. Ricinoleic acid capped CdS gave cubic phase particles whereas castor oil capped CdS gave both cubic and hexagonal phases dependent on the reaction temperature and the type of complex used. The morphology of the particles varied from oval-short rods to spherical shaped particles with sizes ranging from 10 to 22. nm. Rhodamine B (RhB) dye photodegradation studies of a representative CdS nanoparticles' sample have been carried out in the presence of halogen light and studied using UV-visible spectroscopy.Item Synthesis and characterization of PbS nanoparticles in an ionic liquid using single and dual source precursors(Materials Science and Engineering: B, 2018) Tshemese, Zikhona; Khan, Malik D; Mlowe, Sixberth; Revaprasadu, NeerishWe report a green route for the synthesis of PbS nanoparticles in an imidazolium based ionic liquid (IL) (1-ethyl-3-methylimidazolium methanesulfonate) using single source and dual source precursor methods. Lead ethyl xanthogenate complex was used as single source molecular precursor for the synthesis of PbS nanoparticles, whereas in dual source approach organic sulfur (1-dodecanethiol) and inorganic sulfur (sodium sulfide) sources were used to observe the suitability of different sulfur sources on formation of PbS nanoparticles. The results showed that the temperature has an effect on the as prepared nanoparticles for both routes. X-ray diffraction (XRD) studies confirmed formation of cubic phase of PbS from both routes. Electron microscopy techniques showed that the nanoparticle morphologies differed significantly depending on the synthetic factors such as temperature, nature of precursors and ranged from spherical to cubic shapes.Item Tailoring Shape and Crystallographic Phase of Copper Sulfide Nanostructures Using Novel Thiourea Complexes as Single Source Precursors(Journal of Inorganic and Organometallic Polymers and Materials, 2019-05) Ketchemen, Kevin IY; Khan, Malik D; Mlowe, Sixberth; Nyamen, Linda D; Ndifon, Peter T; O'Brien, Paul; Revaprasadu, NeerishCopper sulfide thin films and nanoparticles have been prepared via aerosol assisted chemical vapour deposition and solvothermal hot injection routes, respectively. Both routes employed heterocyclic amine based benzoylthioureato-copper(II) complexes as single source precursors. Copper sulfide thin films of diverse morphologies ranging from cubic to snowy or irregular crystallites depending on the deposition temperature were observed. Powder X-ray diffraction studies of the as deposited thin films have indicated the formation of hexagonal and cubic phases of copper sulfide. In the case of the nanoparticles, Roxbyite (Cu1.75S) phase was obtained in dodecanethiol at temperatures of 150, 190 and 230 °C. However, a preferred growth of nanoparticles was observed in the presence of oleylamine whereas the roxbyite phase was obtained at temperatures of 150, 200 and 250 °C. Also transmission electron microscopy showed the formation of close to spherical, hexagonal nano-disk and rod shaped nanoparticles.Item Thermolytic synthesis of cobalt and cobalt sulfide nanoparticles using Cobalt(II) NO Schiff base complexes as single molecular precursors(Turkish Journal of Chemistry, 2018) Khoza, Sandile H; Masikane, Siphamandla C; Mlowe, Sixberth; Ezekiel, Itegbeyogene P; Moyo, Thomas; Revaprasadu, NeerishTwo novel N^O-type Schiff base ligands and the corresponding Co(II) complexes are reported. Thermo-gravimetric analysis indicated that the complexes are potential molecular precursors for the fabrication of cobalt andcobalt-containing nanomaterials. The significant difference in the thermal decomposition profiles is recognized as aninfluence of structural differences on the complexes. Thus, the complexes were thermally decomposed using the melt andhot injection methods to examine the properties of the obtained cobalt and cobalt sulfide nanoparticles, respectively.The reaction parameters employed during the fabrication processes, in addition to structural differences, influencedthe morphological and crystallographic phases and magnetic properties of the synthesized nanoparticles. We have in-vestigated the morphological properties and the crystallographic phase compositions of the nanoparticles by variouselectron microscopy and diffraction techniques, as well as energy-dispersive X-ray spectroscopy. The melt reactionsproduced phase-pure cobalt nanoparticles, which exhibit ferromagnetic behavior. The hot injection method utilized 1-dodecanethiol (DDT) as both sulfur source and capping agent. We indexed the DDT-capped cobalt sulfide nanoparticlesto cubic Co9S8and Co3S4phases using powder X-ray diffraction, high-resolution transmission electron microscopyimaging, and selected area electron diffraction. The crystallite sizes for Co9S8and Co3S4nanoparticles, based on theScherrer equation, were 12.4 nm and 14.1 nm, respectively. We find significant differences in the magnetic properties,attributed to nonmagnetic inclusions and vacancies due to the presence of S atoms.