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Emmanuel Iwuoha     University Educator/Researcher 
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Emmanuel Iwuoha published an article in February 2019.
Top co-authors See all
Malcolm R Smyth

118 shared publications

School of Chemical Sciences

Vera Cimrova

83 shared publications

Institute of Macromolecular Chemistry

Omotayo A. Arotiba

64 shared publications

Department of Applied Chemistry, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, Johannesburg, South Africa

Jeanine L. Marnewick

46 shared publications

Department of Biomedical Sciences, Cape Peninsula University of Technology, South Africa; and, Oxidative Stress Research Centre, Institute of Biomedical and Microbial Biotechnology, Cape Peninsula University of Technology

L.F. Petrik

45 shared publications

Department of Chemistry, Environmental and Nano Sciences Research Group, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa

202
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Distribution of Articles published per year 
(2003 - 2018)
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22
 
Publications See all
Article 1 Read 0 Citations Graphene Oxide Decorated Nanometal-Poly(Anilino-Dodecylbenzene Sulfonic Acid) for Application in High Performance Superc... Nomxolisi R. Dywili, Afroditi Ntziouni, Chinwe Ikpo, Miranda... Published: 11 February 2019
Micromachines, doi: 10.3390/mi10020115
DOI See at publisher website ABS Show/hide abstract
Graphene oxide (GO) decorated with silver (Ag), copper (Cu) or platinum (Pt) nanoparticles that are anchored on dodecylbenzene sulfonic acid (DBSA)-doped polyaniline (PANI) were prepared by a simple one-step method and applied as novel materials for high performance supercapacitors. High-resolution transmission electron microscopy (HRTEM) and high-resolution scanning electron microscopy (HRSEM) analyses revealed that a metal-decorated polymer matrix is embedded within the GO sheet. This caused the M/DBSA–PANI (M = Ag, Cu or Pt) particles to adsorb on the surface of the GO sheets, appearing as aggregated dark regions in the HRSEM images. The Fourier transform infrared (FTIR) spectroscopy studies revealed that GO was successfully produced and decorated with Ag, Cu or Pt nanoparticles anchored on DBSA–PANI. This was confirmed by the appearance of the GO signature epoxy C–O vibration band at 1040 cm−1 (which decreased upon the introduction of metal nanoparticle) and the PANI characteristic N–H stretching vibration band at 3144 cm−1 present only in the GO/M/DBSA–PANI systems. The composites were tested for their suitability as supercapacitor materials; and specific capacitance values of 206.4, 192.8 and 227.2 F·g−1 were determined for GO/Ag/DBSA–PANI, GO/Cu/DBSA–PANI and GO/Pt/DBSA–PANI, respectively. The GO/Pt/DBSA–PANI electrode exhibited the best specific capacitance value of the three electrodes and also had twice the specific capacitance value reported for Graphene/MnO2//ACN (113.5 F·g−1). This makes GO/Pt/DBSA–PANI a very promising organic supercapacitor material.
Article 1 Read 1 Citation Spectroscopic and Voltammetric Analysis of Platinum Group Metals in Road Dust and Roadside Soil Charlton Van Der Horst, Bongiwe Silwana, Emmanuel Iwuoha, Ve... Published: 02 November 2018
Environments, doi: 10.3390/environments5110120
DOI See at publisher website ABS Show/hide abstract
The emission of toxic compounds by increasing anthropogenic activities affects human health and the environment. Heavy road traffic and mining activities are the major anthropogenic activities contributing to the presence of metals in the environment. The release of palladium (Pd), platinum (Pt), and rhodium (Rh) into the environment increases the levels of contamination in soils, road sediments, airborne particles, and plants. These Pd, Pt, and Rh in road dusts can be soluble and enter aquatic environment posing a risk to environment and human health. The aim of this study is to determine the levels of Pd, Pt, and Rh with spectroscopy and voltammetric methods. Potential interferences by other metal ions (Na(I), Fe(III), Ni(II), Co(II)) in voltammetric methods have also been investigated in this study. At all the sampling sites very low concentrations of Pd, Pt, and Rh were found at levels that range from 0.48 ± 0.05 to 5.44 ± 0.11 ng/g (dry weight (d.wt)) for Pd(II), with 17.28 ± 3.12 to 81.44 ± 3.07 pg/g (d.wt) for Pt(II), and 14.34 ± 3.08 to 53.35 ± 4.07 pg/g (d.wt) for Rh(III). The instrumental limit of detection for Pd, Pt, and Rh for Inductively Coupled Plasma Quadrupole-based Mass Spectrometry (ICP-QMS) analysis was found to be 3 × 10−6 µg/g, 3 × 10−6 µg/g and 1 × 10−6 µg/g, respectively. In the case of voltammetric analysis the instrumental limit of detection for Pd(II), Pt(II), and Rh(III) for differential pulse adsorptive stripping voltammetry was found to be 7 × 10−8 µg/g, 6 × 10−8 µg/g, and 2 × 10−7 µg/g, respectively. For the sensor application, good precision was obtained due to consistently reproduced the measurements with a reproducibility of 6.31% for Pt(II), 7.58% for Pd(II), and 5.37% for Rh(III) (n = 10). The reproducibility for ICP-QMS analysis were 1.58% for Pd(II), 1.12% for Pt(II), and 1.37% for Rh(III) (n = 5). In the case of repeatability for differential pulse adsorptive stripping voltammetry (DPAdSV) and ICP-QMS, good standard deviations of 0.01 for Pd(II); 0.02 for Pt(II), 0.009 for Rh(III) and 0.011 for Pd, 0.019 for Pt and 0.013 for Rh, respectively.
Article 0 Reads 0 Citations Electrochemical determination of phenothrin in fruit juices at graphene oxide-polypyrrole modified glassy carbon electro... Molla Tefera, Merid Tessema, Shimelis Admassie, Emmanuel I. ... Published: 01 November 2018
Sensing and Bio-Sensing Research, doi: 10.1016/j.sbsr.2018.09.003
DOI See at publisher website ABS Show/hide abstract
An electrochemical sensor was developed based on graphen oxide-polypyrrole modified glassy carbon electrode (GO/PPy/GCE) for sensitive determination of phenothrin in fruit samples. GO/PPy/GCE was characterized by scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Ultraviolet-Visible spectroscopy (UV–Vis) and Raman spectroscopy. The sensor was also characterized using electrochemical impedance spectroscopy and cyclic voltammetry. Compared to bare GCE, GO/GCE and PPy/GCE, the reduction peak current of phenothrin increased significantly at GO/PPy/GCE, demonstrating that GO/PPy/GCE exhibited electrocatalytic activity towards the reduction of phenothrin. Under the optimal conditions, the sensor showed a linear relationship over the range of 2.5 × 10−8-2.0 × 10−5 M with detection limits of 13.8 × 10−9 M. In addition, the analytical application of the proposed method was carried out by the determination of phenothrin in fruit juice samples.
Article 0 Reads 0 Citations Orthorhombic Nanostructured Li2 MnSiO4 /Al2 O3 Supercapattery Electrode with Efficient Lithium-Ion Migratory Pathway Miranda Mengwi Ndipingwi, Chinwe O. Ikpo, Ntuthuko Wonderboy... Published: 30 October 2018
Batteries & Supercaps, doi: 10.1002/batt.201800045
DOI See at publisher website
Article 2 Reads 1 Citation Voltammetric and Spectroscopic Determination of Rare Earth Elements in Fresh and Surface Water Samples Martin Makombe, Charlton Van Der Horst, Bongiwe Silwana, Emm... Published: 09 October 2018
Environments, doi: 10.3390/environments5100112
DOI See at publisher website ABS Show/hide abstract
The increasing demand for rare earth elements in green technology, electronic components, petroleum refining, and agricultural activities has resulted in their scattering and accumulation in the environment. This study determined cerium, lanthanum and praseodymium in environmental water samples with the help of adsorptive differential pulse stripping voltammetry (AdDPSV) and inductive coupled plasma-optical emission spectroscopy (ICP-OES). A comparison of the results of these two analytical techniques was also made. The accuracy and precision of the methods were evaluated by spiking water samples with a known amount of REEs. The detection limit obtained for the stripping analysis was 0.10 μg/L for Ce(III), and 2.10 μg/L for combined La(III) and Pr(III). The spectroscopic method of determination by ICP-OES was applied to the same samples to evaluate the effectiveness of the voltammetry procedure. The ICP-OES detection limit obtained was 2.45, 3.12 and 3.90 μg/L for Ce(III), La(III) and Pr(III), respectively. The results obtained from the two techniques showed low detection limits in voltammetry; the ICP-OES method achieved better simultaneous analysis. This sensor has been successfully applied for the determination of cerium, lanthanum, and praseodymium in environmental water samples, offering good results.
BOOK-CHAPTER 1 Read 0 Citations Conducting Polymers and Composites Abd Almonam Baleg, Milua Masikini, Suru Vivian John, Avril R... Published: 22 August 2018
Functional Polymers, doi: 10.1007/978-3-319-92067-2_17-1
DOI See at publisher website
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