Noah Kyame Asare-Donkor

Kwame Nkrumah University Of Science and Technology | KNUST · Department of Chemistry

The ability of photocatalysis to clean up environmental contamination, notably in the treatment of water and air, has received extensive research. The composite materials synthesized by the coprecipitation method were made of ZnO and graphitic carbon nitride (g-C3N4) with various concentrations of lanthanum doping (La-ZnO). It was discovered that L...

Using first−principles DFT calculations and taking into account the impact of in−plane biaxial strain, we thoroughly explore the optical, electronic, mechanical, transport, and photocatalytic properties of Al2OS/Ga2SSe vdWH. The most stable configuration of Al2OS/Ga2SSe vdWH is mechanically, thermally and dynamically stable. Moreover, Al2OS/Ga2SSe...

Surface engineering has been proved as an efficient technique to boost charge separation and visible light absorption of semiconductor photocatalyst materials. Herein, we offer a first insight into the photocatalytic properties and electronic structure of cubic LaAlO3(001) modified with cubic BaTiO3 (001), (011) and (111) surfaces. Compared to the...

A hotspot in renewable energy research is visible-light-driven photocatalytic water splitting for hydrogen production. Monolayer stacking in the form of van der Waals heterojunctions (vdWHs) can be used for band gap engineering and the control of exciton dynamics for prospective nano-electronic devices. Using state-of-the-art hybrid dispersion-corr...

Photocatalytic water splitting for the generation of hydrogen can be achieved by utilizing highly efficient type II van der Waals (vdW) heterostructures as a novel class of materials with a highly tunable bandgap energy and band alignment. Herein, we constructed a CdS/SiH vdW heterostructure by stacking CdS on the top of SiH monolayers and investig...

A suitable electronic structure and efficient charge separation are significant for the performance of photocatalytic water splitting. Herein, we have designed a two-dimensional GeI2/C2N van der Waals (vdW) heterostructure and systematically examined its stability, electronic, photocatalytic, optoelectronic and optical properties, and the effects o...

Detecting toxic gases, especially greenhouse gases, is one of the most challenging and complex tasks to maintain a sustainable environment. Based on first-principles theoritical calculations, we investigate the sensing performance of HCN, NH3 and SO2 gas molecules on GaS ML with and without Ga-/S-vacancy defects. The selectivity was investigated ba...

Cosmetologists may be potentially exposed to high levels of formaldehyde as a result of their exposure to formaldehyde released from the various cosmetic products used in the beauty salons. In order to assess the exposure of cosmetologists to formaldehyde, the indoor air in sixty beauty salons across the ten submetros in Kumasi were sampled to dete...

Groundwater is a major source of drinking-water supply in most developing countries including Ghana. Groundwater samples were collected from boreholes from fifty-seven (57) communities in the Northern and Upper East regions of Ghana between October 2016 and March 2017. Physico-chemical parameters and heavy metals, such as Fe, As, Cd, Pb, Mn, and Zn...

Formaldehyde is the main ingredient in embalming liquids used in mortuaries for preserving bodies. Due to its carcinogenicity, it has raised questions about the occupational health of workers in health facilities that work with formaldehyde. This poses health risk to morticians, hospital workers and mortuary workers. This study measures the formald...

Pressed wood products, carpets, cleaning products such as detergents and disinfectants, and furniture are significant sources of formaldehyde in residential homes and offices. Due to formaldehyde’s carcinogenicity, it has brought into question the impact of indoor air pollutants and indoor air quality. This poses a health risk to the workers and re...

This study evaluates the exposure of the Ghanaian population of the Kumasi Metropolis of Ghana to formaldehyde through the consumption of fish using 3-Methyl-2-Benzothiazoline Hydrazone method, with trichloroacetic acid as an extracting agent. A total of sixty (60) fish species comprising both local and imported fish were bought from cold stores an...

Radon in groundwater and their annual effective dose in the Ashanti region of Ghana have been determined using the continuous grab sampling technique and an AB-5 detector. Mean levels of radon were in the range of 0.51–46.16 Bq L−1. Effective annual doses ranged from 0.18–16.16, 0.13–12.08 and 0.09–8.31 μSv y−1 for infants, children and adults, res...

Background: Geogenic and anthropogenic activities such as Artisanal and illegal gold mining continue to have negative impacts on the environment and river basins in China. This work studied the hydrogeochemical characteristics of surface water from the Birim River basin and assess the quality of water for human consumption and agricultural activiti...

Geogenic and anthropogenic activities introduce certain metals into the environment which tend to deteriorate the quality of both surface and groundwater in the Bosomtwe Crater Lake and its surroundings. In this study spatio-temporal variations in concentrations and risk assessment of selected trace metals (As, Fe, Pb, Zn, Cr, Cd and Ni) were inves...

Background: The phosphinato complexes of group IIB are of great interest for their potential toward technological applications. A gas phase mechanistic investigation of the chemical vapour deposition of cadmium chalcogenides from the decomposition of Cd[(C6H5)2PSSe]2, as a single source precursor is carried out and reported herein within the framew...

Background Mercury (Hg) used in gold amalgamation is a major source of contamination in developing countries. The present study evaluates the concentrations of total mercury in water, sediment and fish from the Ankobra and Tano Rivers, which drain the major gold mining areas in Ghana. Total mercury (T-Hg) analysis was carried out using an atomic ab...

The concentrations of four heavy metals (Pb, Cd, Cu and Fe) were determined in water, sediments, Galatea paradoxa (clam) and Macrobrachium raridens (Prawn) from Ada fishing site at the Volta Estuary in Ghana using Atomic Absorption Spectrophotometer (AAS). The mean metal concentrations in water were 0.21, 0.02, 1.74 and 0.04 mg/kg for Pb, Cd, Cu an...

Surface water represents significant source of fresh water for irrigation and drinking purposes and therefore preserving the availability and quality of this resource is extremely important. Surface water samples within the catchment area of the Obuasi mine were analysed to assess dissolved concentrations, hydrochemistry, risk evaluation of selecte...

The mechanistic pathways for the formation of zinc selenide, zinc sulphide and ternary zinc selenide sulphide in the gas phase decomposition of Zn[(C6H5)2PSSe]2 single-source precursor has been explored on the singlet and doublet potential energy surfaces using density functional theory method in order to understand the thermodynamic and kinetic pr...

The reaction mechanism of the gas phase decomposition of Pb[(iPr)2PSSe]2 single-source precursor has been investigated theoretically by means of the density functional theory (DFT). The geometries of all the stationary points and the selected points along the potential energy surfaces were optimized at the M06/LACVP* level of theory. The harmonic v...

A theoretical study of Pb(II) square planar thioselenophosphinate, Pb[(C6H5)2PSSe]2 precursor for the chemical vapour deposition process of preparing lead chalcogenides, has been carried out. The geometries of the species were optimized by employing the density functional theory. The transition states as well as the linked intermediates linking the...

The chemistry of group II–VI semiconductors has spurred considerable interest in decomposition reaction mechanisms and has been exploited for various technological applications. In this work, computational chemistry was employed to investigate the possible gas-phase decomposition pathways of the mixed Cd[(iPr)2PSSe]2 single-source precursor for the...

Cadmium sulphide thin films have been prepared by the chemical bath deposition technique (pH 11, 70oC). Two different sets of films were prepared under varied conditions and concentrations of their ions sources (Cd2+ from cadmium nitrate, S2- from thiourea) and Na2EDTA as a com-plexing agent. A UV mini Schimazu UV –VIS Spectrophotometer was used to...

A field investigation was conducted to assess the breakdown of azadirachtin A in a tropical coastal savanna soil amended with neem leaves (NL) combined with poultry manure (PM) or cow dung (CD) using gas chromatography. Samples in polythene bags 15 cm long and 4.8 cm in diameter were randomly placed to a depth of 14 cm in the soil, and azadirachtin...

ABSTRACTA field investigation was conducted to assess the breakdown of azadirachtin A in a tropical coastal savanna soil amended with neem leaves (NL) combined with poultry manure (PM) or cow dung (CD) using gas chromatography. Samples in polythene bags 15 cm long and 4.8 cm in diameter were randomly placed to a depth of 14 cm in the soil, and azad...