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This study aims to investigate the influence of SILAR cycle on the energy bandgap of Iron Copper Sulphide (FeCuS) thin films deposited on soda-lime glass substrate (SLG). A Successive Ionic Layer Adsorption and Reaction (SILAR) method is one of the chemical methods for making uniform and large area thin films, which is based on immersion of substrates into separately placed cationic and anionic precursors. The technological importance of chemically deposited iron copper sulphide (FeCuS) using SILAR technique vis-à-vis the effect of SILAR cycle on the energy band gap of the deposited thin films has not been unraveled. Thin films of Iron Copper Sulphide were grown on soda-lime glass substrate (SLG) by a simple solution based Successive Ionic Layer Adsorption and Reaction (SILAR) technique at room temperature (300 K) with EDTA, TEA and NH 4 OH as complexing agents at different SILAR cycles (20, 30 and 40 cycles) of deposition. The thin films grown were characterized using Avantes UV-VIS spectrophotometer (Avalight-DH-S-BAL) in the wavelength range 200-1000nm and Four Point Probe machine (Keithley 4ZA4 2400 Sourcemeter, manufactured by Tektronix Company). The optical properties considered revealed high absorbance and reflectance but low transmittance in the UV region; low values of absorbance and reflectance accompanied with high transmittance in the VIS region. Moreover, the resistivity of the grown thin film varied from 9.480 x 10 6 Ωm to 4.366 x 10 7 Ωm in order of increasing SILAR cycle, direct band gap of 3.76e V, 3.51e V and 3.42e V were obtained. These properties suggest that the films are suitable for solar cell and optoelectronic applications.

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Environmental pollution is a global phenomenon which could results from both natural and anthropogenic activities which has resulted to several health and physiological problems in both plants and animals. Dump sites’ soils of and Borehole waters from Ojota, Ebutte-Meta, Igando and Bariga in Lagos state were analyzed for heavy metals using atomic absorption spectrophotometer. The data obtained were further subjected to contamination factor and pollution indices analyses. The results obtained showed lead (Pb) to be most concentrated in the soils and ranged from 0.22 ppm to 2.50 ppm, this was followed by the value recorded for zinc (Zn) which was between 0.0015 ppm to 0.020 ppm. The least observed metal in all the soil sample stations was nickel (Ni) which ranged from 0.001 ppm to 0.010 ppm. On the other hand, only water samples from Ojota and Ebutte-Meta were detectable with Pb concentration values of 0.38 ppm and 0.0028 ppm, Ni concentration values of 0.0052 ppm and 0.009 ppm, Zn concentration values of 0.0039 ppm and 0.0020 ppm respectively. On subjecting the concentration of the heavy metals to contamination factor (CF) revealed very slight contamination of the different soils from different areas. There was also very slight contamination of the waters from Ojota and Ebutte-Meta by metals, except for Igando and Bariga that were moderately and severely contaminated by the metals respectively. The Pollution Index (PI) showed that the soils and waters samples are unpolluted with the heavy metals.