Thin films of zinc sulfide (ZnS) with different concentrations of zinc acetate have been made by chemical bath deposition technique in acidic medium (pH = 5) on glass substrate using zinc acetate and sodium sulfide as sources of Zn+2 ion and S−2 ion, respectively, and ethylenediaminetetraacetate as complexing agents and sulfuric acid to adjust pH value at a constant deposition temperature of 85°C, and the deposition time of 90 minutes was used. The effect of the concentration of metallic precursor on the structural, morphological, and optical properties of chemical bath deposited zinc sulfide thin films was investigated in this study. The XRD result confirmed mixed phases of crystalline and amorphous structure dominating other phases, which is witnessed by larger crystallite size than other phases. It reveals that the thin films had hexagonal structure at the medium concentration with preferred orientation along (111) plane, and at lower and higher concentration, it showed that film has an amorphous structure in nature. The crystallinity of all the phases significantly enlarged with increasing the zinc precursor concentration. The SEM micrographs showed high-pitched edged irregular-shaped grains covering the substrate with pinholes and bangs. The optical properties investigated by the UV-VIS spectrometer specified a decrease in the optical bandgap of the films between 3.5 eV and 2.6 eV as the zinc acetate concentration in the solution increased from 0.1 to 0.2 M. It showed that the zinc sulfide had high absorption in the UV radiation. The main finding of this paper is that metallic precursor concentration has a significant role in the optical, morphological, and microstructural properties of the cobalt sulfide thin films, which are most suitable for photovoltaic applications.

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This research is based on the characterization of khat waste (Catha edulis) through the use of some experimental approaches required to produce a clean, renewable energy source that could enhance our environmental economy as well as our energy security. The objective of this article is to characterize the pyrolysis khat waste in both proximate and ultimate analysis, thermal decomposition (weight loss of khat), and functional categories of khat waste, by using a Fourier transform infrared spectroscopy to determine the functional group of a sample. We also used an elemental analyzer device (model: Thermo Scientific–EA1112 FLASH CHNS/O analyzer) to measure elemental composition, characterize the proximate analysis of khat, and measure weight loss or thermal behavior of raw khat sample by using a device called thermogravimetric analyzer (TA instrument model: SDT Q600). The determined characterization of the khat sample was 48.25 percent carbon, 6.16 percent hydrogen, 45.13 percent oxygen, and 0.46 percent nitrogen. When compared to coal, khat contains extremely little nitrogen, resulting in less environmental contamination to the air than fossil fuel combustion. The proximate analysis results of the khat sample also showed 5 percent and 5.26 percent moisture content for both wet and dry bases, respectively, as well as 76.3 percent volatile matter, 4.8 percent ash content, and 13.83 percent fixed carbon. The findings are discussed in this research by comparing the final value results with other biomass and coil. The functional group of khat waste was studied using a spectrum of (65 Perkin Elmer) at wavelength ranges of 4000 to 400 cm-1. The weight loss of the khat sample at 700°C and a heating rate of 20°C/min, as well as the proximate analysis of this raw khat, were 4.5 percent, 75.84 percent, 5.38 percent, and 14.28 percent for moisture, unstable substance, ash content, and static carbon, respectively. The differences between TGA values and the projected proximal value were 10%, 0.6 percent, 9.47 percent, and 3.15 percent for moisture, volatile matter, as content, and fixed carbon, respectively. Overall, the benefit we get from pyrolysis of khat waste is that khat waste has very low nitrogen content and empty sulfur, which is very important for reducing air pollution and environmental sanitation when used as fuel. So from pyrolysis, khat waste types of fuel such as biochar, liquid fuel, and gas fuel can be obtained.

Biological approach synthesis and characterization of Iron Sulfide (FeS) thin films from banana peel extract for contamination remediation of environment studied. Iron chloride, Sodium thiosulfate and Ethylene-di-amine-tetra acetate (EDTA) were used as precursor solutions without further purification. The nanoparticle of banana peel was extracted and prepared with synthesized FeS thin films and analyzed by X ray-diffraction for structural examination, Scanning electron microscope (SEM) for surface morphological analysis, Ultra-violet-visible-spectrometer (UV–Vis) and photo-luminescence spectro-photo-meter (P-L) for optical characterizations. XRD peaks are shown with recognized to (110), (200), (310), and (301) crystalline planes. The occurrence of this deflection peak are recognised the FeS crystal segment of the tetragonal crystalline systems. SEM micrographs of the films prepared biological method show the distribution of grains, which cover the surface of the substrate completely and are uniform and films deposited purely have defects. The photo-luminescence, absorbance, and transmittance strength of banana peel extract FeS thin film is greater than pure FeS thin films in which wide-ranging and symmetries groups were perceived. In the present study, the comparison of pure FeS thin films and Nano synthesized banana peel extract with FeS thin films was studied. It is observed that Nano synthesized banana fibre absorbs higher than pure FeS thin films in solar cell application. Finally, green synthesis is an ecofriendly, easy and cheap promising method for the fabrication of thin films for solar cell applications.

The melt-quenching technique was used to produce 39CdO–10Al2O3-(51-x) P2O5: xMnO glasses (x = 0, 0.1, 0.2, 0.3, and 0.4 wt.%). Various stability factors were calculated and presented from DTA analysis. The stability of the glass network appears to increase with the increase of MnO concentration, according to the findings. IR spectral analysis of these glasses exhibited several symmetrical and asymmetrical bands due to phosphate groups. The observed change in these band intensities with the rise in MnO concentrations, ranging from 0.1 wt.% to 0.4 wt.%, shows an increase in the stability of the glass network. Optical absorption analyses of these glasses revealed an absorption band that shifted from 500 to 488 nm as the concentration of manganese oxide (MnO) increased from 0.1 wt.% to 0.4 wt.%, indicating that Mn2+ ions were gradually converted into Mn3+ ions. EPR spectra of these glasses were characterized by two signals due to Mn2+ and Mn3+ ions. Observations on these signal intensity variations revealed an increase in stability of the glass network with the increase of MnO concentration from 0.1 wt.% to 0.4 wt.%. Parameters, which describe the insulating characteristics, for example, dielectric constant, ε, dielectric loss, tan δ, and AC conductivity σac, were determined in relation to frequency (103 Hz to 105 Hz) and temperature (20°C to 400°C) and presented in the dielectric analysis of these glasses.