Scopus Research — Yassin Hasan Kadhim

NiO thin films, both pure and Li-doped, were created by depositing films onto base substrates. The produced films for Li doping exhibited a cubic structure, as confirmed by the XRD patterns. AFM analysis of NiO and NiO: Li (300 nm) shows surface roughness: Sz (25.70–35.62 nm), average (3.346–4.390 nm), RMS (4.1195–5.336 nm). SEM reveals morphological changes: Undoped NiO, NiO: 2% Li, and NiO: 4% Li films exhibit nanostructure evolution correlated with Lithium doping. According to an optical investigation, Li doping reduces the band gap. The sample with 2% Li doping had the lowest value. The first principal technique based on density functional theory was employed to analyze the structural, optical, and elastic properties of pure NiO and 4% Li-doped NiO. The lattice parameters are altered upon doping by optimizing the samples’ geometrical characteristics. According to the band structure calculations, the undoped and Li-doped samples displayed a straight band gap, while band gaps of doped NiO were relatively smaller. © Australian Ceramic Society 2025.

CdS, and CdS: Al were grown onto glass bases via Chemical spray pyrolysis (CSP). XRD analysis of CdS films indicates a polycrystalline hexagonal structure with a predominant orientation of the (101) plane. The strain decreased from 28.55 to 25.66, and the grain size of undoped CdS films was around (13.51–12.14) nm as Al content rose. According to the results of AFM, CdS, CdS:2% Al, and CdS:4% Al all exhibit smooth surfaces with decreasing particle size in the range of (78.46), (69.75), and (42.20) nm, respectively. The root-mean-square roughness values for CdS and CdS:4% Al were 12.41 nm and 3.38 nm. According to AFM image, the surface roughness of CdS to CdS:4% Al were (9.74-5.16) nm. SEM images depict CdS films transitioning from flat islands (Undoped CdS) to uniform spherical nano-grains with Al doping. The result shows a decrease in absorption coefficient as Al content increased. The optical bandgap increased from (2.35-2.51) eV after doping. Results show that the extinction coefficient and refractive index are influenced by Al content. CdS film detects NO2 gas by resistance increase, impacted by Aluminum doping. Sensitivity decreases with an increase in Al doping in CdS films. © 2025, S.C. Virtual Company of Physics S.R.L. All rights reserved.

Using chemical bath deposition (CBD) methods and various molarities, nanostructured CdS thin films were developed. XRD assured that these films were cubic polycrystalline, containing larger grains as the solution's concentration of cadmium ions increased. Dislocation density values dropped from 79.32 to 62.90 as a result, nevertheless. Also, the strain is lowered from 30.88 to 27.50. AFM results demonstrate that these films suffer a decrease in the value of average particle size, root mean square, and roughness with the molarity concentration. SEM images show CdS thin films at various molarities (0.10, 0.15, 0.20) M, indicating reduced grain size with increased concentration. The optical characteristics indicate a large band gap decreases from 2.46 eV to 2.34 eV and a high transmittance in the visible portion of the spectrum of more than 97.5%. The Refractive Index value changed from 3.23 to 3.11 as the content of cadmium ions increased. CdS films show p-type behavior, reducing resistance with NO2 gas, influenced by molar concentration. The sensitivity of CdS films to NO2 shows a decrement with increased molar concentrations. © 2025, S.C. Virtual Company of Physics S.R.L. All rights reserved.

TiO2 thin films were deposited utilizing chemical vapor deposition. XRD data indicate that all the films were polycrystalline with a predominat plane along (121). As the dislocation density and strain parameter reduce from (91.15 to 64.13), (31.97 to 27.76 For film thicknesses of 250 nm and 350 nm, respectively. the grain size increases from 10.45 nm to 12.48 nm with an increase in thickness from 250 to 350 nm. AFM images revealed that average particle sizes were 80.1 nm to 24.8 nm as thickness increased, whereas surface roughness averages decreased as film thickness increased. SEM images reveal thin film surfaces (TiO2) (250, 300, 350 nm), and reduced grain size indicates finer particles. With increasing thickness, it is discovered that the band gap and the film's transmittance both decreases. It was found that as film thickness increases, so do absorption and absorption coefficient. The direct band gap dropped from 3.28 to 3.15 eV with the increase in thickness. The calculated extinction coefficient of the films with different thicknesses was reduced from 0.58 to 0.55. The gas sensor tested with NO2 exhibited increased resistance at 300 ppm, indicating high sensitivity. TiO2 film with a thickness of 350 nm showed the highest resistance. Sensitivity decreased with higher thicknesses (250, 300, and 350 nm) for NO2 gas, with reductions observed: 33.4% to 10.9% (100 ppm), 35.4% to 12.5% (200 ppm), and 37.2% to 14.8% (300 ppm). © 2025, S.C. Virtual Company of Physics S.R.L. All rights reserved.

Nanostructured thin films of Iron (Fe)-doped Zinc Sulfide (ZnS) were deposited via the Chemical Spray Pyrolysis (CSP) technique, with varying concentrations of Iron incorporated into the ZnS matrix. XRD analysis confirmed that all films preserved a zinc blende cubic structure, while the calculated average crystallite size increased from 13.25 nm for pure ZnS to 14.8 nm for Fe-doped samples. The structural investigation further demonstrated that Iron incorporation influenced lattice parameters, microstrain, and dislocation density, thereby reflecting measurable changes in overall crystal quality. Atomic Force Microscopy (AFM) revealed a relatively smooth and uniform surface topography, supporting the good quality of the prepared thin films. Optical properties were systematically examined using UV-Visible spectroscopy, which showed a clear dependence of band gap energies on Fe concentration, indicating that Fe ions effectively substituted Zn sites. Gas sensing measurements toward NO2 at 125°C highlighted that Fe doping generally reduced sensitivity; however, thinner films exhibited enhanced responsiveness due to their larger surface-tovolume ratio and the presence of more active interaction sites. These results suggest potential for tailoring ZnS-based materials in optoelectronic and sensing applications. © 2025, Anhalt University of Applied Sciences. All right reserved.

Fe₂O₃:Al (1–3 at%) thin films were successfully grown on glass substrates at 400°C using the chemical spray pyrolysis (CSP) technique. The X-ray diffraction (XRD) patterns confirmed the formation of α-Fe2O3 with a prominent (104) peak, indicating high crystallinity. The average grain size (D) increased from 15.82 nm to 18.70 nm with increasing Al content, while the lattice strain (ε) decreased from 2.18 to 1.85, suggesting improved crystal quality. Atomic Force Microscopy (AFM) analysis showed a reduction in surface roughness and uniform particle distribution, with particle diameters ranging from 65.5 nm to 52.31 nm. Optical studies revealed a gradual narrowing of the bandgap values from 2.81 eV (undoped) to 2.74 eV, 2.69 eV, and 2.64 eV for 0 at%, 1 at%, and 3 at% Al-doping levels, respectively. Furthermore, gas sensing tests demonstrated that higher Al doping increased resistance and reduced sensitivity toward NO2 gas due to enhanced charge carrier recombination and altered surface interactions, indicating significant influence on semiconductor gas sensing properties. © 2025, Anhalt University of Applied Sciences. All right reserved.

Indium-doped ZnS samples with doping levels of 0%, 1%, and 3% were fabricated using the chemical spray pyrolysis (CSP) method. XRD patterns confirmed the presence of a cubic zinc blend structure of both pure and Indium-doped ZnS samples. The crystallite size slightly increased with the concentration of indium, attributed to the substitution of indium within the ZnS lattice. AFM provided microscopic insights into the surface structure, allowing for the visualization and characterization of surface topographies. SEM images show transformation in ZnS films with Indium doping: flat islands to spherical nano-grains, indicating size reduction correlating with Indium concentration, influenced by ZnS-Indium interaction during synthesis. The optical parameters of nanostructures were investigated with doping and the incorporation of indium substitute for Zn ions. Indium doping in ZnS films increases resistance and alters gas sensing properties by affecting charge carrier mobility and adsorption efficiency. Higher Indium doping in ZnS films reduces sensitivity to NO2 gas due to changes in charge carrier mobility and film structure. © 2025, Anhalt University of Applied Sciences. All right reserved.

Fluorine-doped α-Fe2O3 nanostructure films were synthesized by a facile Chemical Spray Pyrolysis (CSP) technique at a substrate temperature of 400 °C using standard glass slides. The fluorine dopant concentration was varied incrementally at 0%, 2%, and 4% by weight in order to systematically investigate its influence on the structural, morphological, and optical properties of the deposited films. X-ray diffraction (XRD) analyses exhibit well-defined diffraction peaks corresponding to the (017), (113), (119), and (220) planes, confirming the successful formation of the pure α-Fe2O3 (hematite) phase without any detectable secondary phases. The average crystallite size of hematite increased from 13.98 nm to 16.78 nm with rising fluorine content, indicating enhanced crystal growth and improved crystallinity due to doping. Atomic Force Microscopy (AFM) images reveal uniformly distributed grains with a smooth surface texture free of cracks or pinholes. Furthermore, the surface morphology and grain dimensions were noticeably altered as the dopant concentration increased. Optical characterization demonstrated a progressive decrease in transmittance with fluorine incorporation, reaching 65% at 600 nm, accompanied by a clear blue shift in the optical band gap, indicating modified electronic transitions and enhanced optical activity in the doped films. © 2025, Anhalt University of Applied Sciences. All right reserved.

Li-doped titanium oxide thin films are grown through Spray Pyrolysis (SP) method. XRD peaks showed that samples were polycrystalline. The appropriate peak was at (121) equivalent to 2θ = 30.70◦, the Grain size (D) increased from 9.58 nm to 10.17 nm, whereas strain (ε) decreased from 36.17 to 34.08, whilst dislocation density (δ) decreased from 108.96 to 96.68. According to the AFM photo, surface roughness declined (8.08 - 3.67) nm when TiO2 was increased to 4% Li. The average particle size values were 88.78, 85.62, and 60.89 nm for TiO2, TiO2:2% Li, and TiO2:4% Li, respectively. The transmittance of TiO2 and TiO2: Li films reduced from 85 TiO2% to 75% as Lithium content rise from 1 to 4 at%. Research indicates that the absorption coefficient reduces as the lithium content rises, whereas the bandgap energy, extinction coefficient, and refractive index decline as the lithium content rises. The TiO2gas sensor showed increased resistance at 200 ppm NH3, with 4% Li doping having the highest. Higher Li doping in TiO2 decreases sensor sensitivity to NH3 gas, with a reduction at all concentrations. © 2025, Anhalt University of Applied Sciences. All right reserved.

This study uses glass substrates to create nanostructured TiO2 thin films employing Sol-Gel method. Afterwards, TiO2 films are annealed in air for two hours at (400, 450, and 500) °C. The XRD tests demonstrate that all films are tetragonal polycrystalline and have orientations equal to those described in the literature. These findings suggest that when the annealing temperature rises, grain size increases. As the annealing temperature is raised, the Full Width at Half Maximum (FWHM) reduces from 0.57° to 0.0.51°, and the dislocation density drops from 45.22 to 39.22.18 nm, respectively. AFM has examined the thin films' surface morphology. The films formed using this method have good crystalline and homogenous surfaces, according to AFM tests. With an increase in annealing temperature, thin films' average particle size, average roughness, and Root Mean Square (RMS) value all drop. The films' optical characteristics. The transmission was over 97% decreased with increasing annealing temperatures. It is found that the band gap decreases from 3.42 to 3.3 eV with increasing annealing temperature. Between 300 and 900 nm, the films' refractive indices range from 2.89 to 2.2.76. With higher annealing temperatures, the films' extinction coefficients fall. © 2024, S.C. Virtual Company of Phisics S.R.L. All rights reserved.

In these studies, radio frequency (RF) magnetron sputtering was used to produce nanostructured CuO thin films on glass bases with different thicknesses of (250, 300, and 350 nm). X-ray diffraction (XRD) analysis of these films revealed a polycrystalline structure with a preferred peak along the (111) plane. The Scherrer formula was used to compute the grain size. It was found that the average grain sizes are 10.78 nm, 11.36 nm, and 11.84 nm for film thicknesses of 250, 3000, and 300 nm, respectively, while the dislocation density and strain values decline. The surface roughness decreased from 9.30 nm to 4.71 nm as the thickness increased, according to atomic force microscopy (AFM) data. As the thickness of the film grew, the root mean square (RMS) roughness likewise decreased from 9.18 nm to 4.29 nm. The homogenous, semi-spherical structure comprises uniformly distributed particles, as demonstrated by SEM images. The optical properties of the grown films showed that the absorption coefficient considerably increased with film thickness. Transmittance, band gap, refractive index, and extinction coefficient all decrease with increasing film thickness. The hydrogen gas measurements, indicated a reduction in sensitivity as the thickness and gas concentration increased at 30°C. © 2024, S.C. Virtual Company of Phisics S.R.L. All rights reserved.

This work employed the chemical bath deposition (CBD) technique to fabricate a thin layer of nanostructured MnO. According to XRD measurements, the films have a cubic crystal structure and are polycrystalline, with orientations of (111, 200, 311, and 222), with (200) being the preferred orientation. Although the dislocation density parameters (100.46 to 80.36) and strain decreased from 34.75 to 31.08 and 34.75 to 100.36, respectively, the grain size was largest at (200) nm film thickness and lowest at (300) nm thickness. The deposited films exhibited a smooth surface topography as evidenced by the average surface roughness dropping from 8.70 nm to 4.27 nm, the average particle size observed to be 82.8 nm to 39.2 nm, and a reduction in root mean square (rms) values from 6.82 nm to 3.09 nm in the AFM images. Nanostructured MnO films exhibit a variety of grain morphologies, polycrystalline structure, and uniformity in SEM images. Their optical properties were measured in the 300–900 nm wavelength range. The extinction coefficient ranged from 0.368 to 0.276, whereas the computed refractive indices of the films with varying thicknesses fell between 3.6 and 2.95. The transmittance ranged between 86 and 81% in the VIS-NIR region with a band gap between 3.24 and 3.13 eV, and it was found that the absorption and absorption coefficient increased with film thickness. The thickness of MnO reduces its sensitivity to H2S gas. © 2024, S.C. Virtual Company of Phisics S.R.L. All rights reserved.

Undoped and Chromium (Cr) doped (2, 4%) copper sulfide (Cu2S) nanostructured thin films were created by spray pyrolysis. The films were polycrystalline and combined cubic and monoclinic structures, according to the results of the XRD investigation. Surface roughness values for the doped and undoped thin films are 8.71, 7.79, and 3.24 nm, respectively. SEM images display Cu2S nanostructures with fine crystallites and traces of nanorod. Chromium doping increases particle size and induces nanorod growth, enhancing surface porosity. The optical examination shows that Cr-doped Cu2S thin films exhibit effective absorption (> 104 orders) in the visible range. From the change in absorption coefficient, it can be observed that there is a valley around 2.6 eV. By doping Cr (up to 2%) in Cu2S films, it is possible to control the band gap between 2.62 eV and 2.73 eV. The refractive index of undoped Cu2S films decreases with increasing Cr-doping concentration. Gas sensing of Chromium-doped and undoped Cu2S nanostructures involves dynamic resistance change at 100°C. Undoped Cu2S displays low resistance, exhibiting p-type semiconductor behavior. Notably, 4% Cr-doped Cu2S shows high resistance, and the introduction of NO2 decreases resistance. Decreased sensitivity with rising Cr doping in Cu2S: 2% Cr and Cu2S: 4% Cr. Responsiveness declined across different NO2 concentrations (200 ppm, 300 ppm, and 400 ppm). © 2024, S.C. Virtual Company of Phisics S.R.L. All rights reserved.

This investigation used sol-gel deposition to create undoped CuO and CuO: Cd thin films. All films of undoped CuO and CuO: Cd phase exhibit four dominating peaks at 35.52°, 38.84°, 53.37°, and 68.23°, which are correspondingly assigned to the (022), (200), (020), and (220) planes, according to X-ray diffraction analysis. The dislocation density reduced from 60.55 to 49.94, the strain decreased from 26.98 to 24.60, and the grain size of the produced films measured by XRD was 12.85–14.15 nm. Atomic force microscopy (AFM) was used to study the morphology. SEM analysis showed increased aggregation with higher Cd content, resulting in a more uniform porous structure. The optical band gap decreases for all samples as the cadmium content increases, ranging from 2.28 to 2.14 eV. Similarly, the refractive index and extinction coefficient values decrease as the cadmium content increases for all samples. The gas sensor detects H2 (375 ppm) using CuO film cadmium doping, which enhances sensitivity, CuO: 4% exhibits highest resistance. Sensitivity decreases with higher doping, indicating reduced sensor responsiveness. © 2024, S.C. Virtual Company of Physics S.R.L. All rights reserved.

Nanostructured Tin-doped Fe2O3 with a volumetric concentration of (1% and 3 %) Tin were deposited using spray pyrolysis (SPM). The most substantial peak, as determined by X-ray diffraction, corresponds to the (200). The average particle size values from AFM imaging for the deposited films decreased from 81.52 nm to 40.05 nm. The average roughness was observed to drop from 8.26 nm to 45.38 nm. The Root mean square roughness was lowered from 7.48 nm to 4.86 nm. The strain decreases from (27.92 to 23.69) x10-4. SEM images show morphological changes in Fe2O3 film's big islands after Tin doping. The optical transmittance is outstanding for Undoped Fe2O3 and 3% Sn doping, with 80% and 75 %in the visible zone. It was shown that the absorption coefficient increased as the concentration of Tin was raised. The Fe2O3 bandgap was reduced from 2.80 eV for Fe2O3 to 2.60 eV for Fe2O3: 3 % Sn film. Resistance in Fe2O3 and Tin-doped films rises in NO2 (270 ppm) exposure, indicating an oxidation process. The 3% Tin-doped film shows the highest resistance. Sensitivity declined with increasing Tin content following NO2 exposure. © 2024, S.C. Virtual Company of Physics S.R.L. All rights reserved.

Using Chemical Bath Deposition (CBD) Method and various substrate temperatures, Fe2O3 films were successfully deposited. The produced film thickness was around (320 nm). Using X-ray diffraction, researchers may examine the polycrystalline structure of Fe2O3 thin films. These nanofilms contain strong peaks at 2θ =32.21, suggesting a preferred orientation along the (110) plane, and the grain size increases with substrate temperature, according to XRD tests. When the base temperature was raised from 350 to 450oC, the strain parameter decreased from 31.35 to 28.43. AFM testing of the surface morphology of the deposition of material yields excellent homogenous coatings. The findings show that the average particle size of the nanoparticles ranges from (69.8 to 32.7) nm. SEM images show Fe2O3 films at (350, 400, 450) °C. Increased temperature reduces grain size, influencing morphology variations. The absorbance increases with substrate temperatures and decreases rapidly at short wavelengths, which correspond to the energy gap. The transmittance increases with increasing wavelength range. It decreases with rising substrate temperatures. The band gap values vary from 2.17 eV to 2.06 eV by increasing the substrate temperatures from 350 to 450oC. It was discovered that the band gap reduces as the temperature of the Fe2O3 substrate increases. In addition, the optical constants for all films, including the absorption coefficient, the refractive index, and the extinction coefficient, were computed. Fe2O3 film's resistance over time at 350, 400, and 450°C for 300 ppm NO2 demonstrates oxidation effect and temperature sensitivity. Sensitivity decreases with higher base temperature due to charge carrier recombination, affecting NO2 response. © 2024, S.C. Virtual Company of Physics S.R.L. All rights reserved.

Nanostructured MgO:Fe was fabricated by spray Pyrolysis technique (SPT). XRD verifies MgO's cubic structure. The MgO thin film's crystallite size increased to 10.7–15.41 nm due to doping. SEM pictures display The surface becomes rougher and the grain size increases with concentration. The ideal MgO's average transmission value in the visible spectrum was 70%. The Tauc relation was used to calculate Eg, which decreased for MgO:Fe doping at 4%wt concentration from 362.1 to 3.52 eV. Resistance change as a measure of film sensitivity to gas indicates that MgO is a p-type semiconductor, with the maximum resistance being shown by MgO:Fe at 4%wt. The sensitivity of MgO films to NO2 diminishes as Fe content increases. © 2024, S.C. Virtual Company of Physics S.R.L. All rights reserved.

Using the chemical spray pyrolysis (CSP) technique, nanostructured undoped and Co3O4:In thin films are deposited. The effect of indium doping content in Cobalt ranged from 1% to 3% on optical, structural, and topographical properties of Co3O4 nanostructured thin films. No new peaks belonging to the In phase were seen, according to X-ray diffraction research, which revealed that pure and Co3O4: In thin films are polycrystalline in and cubic phase with (111), (311), (400), and (511) preferable orientation for all filmsThe Scherrer formula computation of average crystallite size shows that the size of Nano crystallites grows when doping is enhanced. AFM micrographs demonstrated how the surface shape of the films was discovered to be influenced by the inclusion of indium in the Co3O4 location.SEM images of Undoped Co3O4 and Co3O4:In films (CSP technique), showing separate semi-spherical blocks (120-200 nm) of nanoparticles (<30 nm). Band gap values for pure and doped were 2.52 to 2.38 eV. Resistance increases with increases Indium-doping, indicating more charge carriers and potential surface roughness influence. Sensitivity decreases with higher Indium concentrations, attributing to enhanced crystallinity and nano-crystalline size. © 2024, S.C. Virtual Company of Physics S.R.L. All rights reserved.

TiO2 and TiO2:Cu films were deposited by spray pyrolysis (SP). X-ray diffraction reveals that deposited films have a polycrystalline structural. The AFM image of the surface reveals that roughness and root mean square affected by doping. Optical transmission of films was found to decrease from 94 % to 84 % with the as the doping percentage increase to 3. Optical bandgap (Eg) of TiO2 thin film was 3.947eV. The bandgap is shifted to lower energies upon doping. © 2023, S.C. Virtual Company of Phisics S.R.L. All rights reserved.

Thermal evaporation technique has been used to produce silver oxide (AgO). The findings demonstrate that the crystal quality of the AgO film was dominated by the thin and sharp peaks at (111) plans. Atomic Force Microscopy (AFM) confirm that the distribution grains size appears nanostructure and homogeneous in all films. RMS decreased from 6.84 nm to 2.17 nm with thicknesses 200 nm. The surface roughness decreased from 7.82 nm to 3.22 nm. The distribution of grains size appears nanostructured and homogeneous in all films, and a slight decrease in average particle size. The surface displayed that the roughness decreased with the increase in thicknesses. The spectrum fluctuation of their optical constants has been calculated using transmittance and absorption data. In the visible region of the wavelength, all films have a high absorption coefficient with a value of 104 (cm-1). According to the optical measurements, the films have a band gap between 1.73 and 1.61 eV. The Extinction coefficient and refractive index drop as film thickness rises. © 2023, S.C. Virtual Company of Phisics S.R.L. All rights reserved.