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Indium doped Tin Oxide (ITO) substrate was used to synthesize Cu and Cu-TiO2 nanocrystals via electrochemical deposition method. The techniques used for analyzing the structure, morphology, optical, magnetic and electrical properties include X-ray diffractometry, scanning electron microscopy, energy dispersive Xray (EDAX), UV-visible spectrophotometer, It was discovered that the energy bandgap shrank from 3.3 - 3.1 eV. The magnetic analysis showed a characteristic ferromagnetic ordering, with 5.13×10-4 emu/g for the 3% and 6.08×10-4 emu/g for the 5% samples, respectively. The maximum conductivity of 0.08 Ωcm-1 was recorded by the 5% doped thin film. [ABSTRACT FROM AUTHOR]

Gel polymer electrolytes were produced using cashew tree gum exudate dissolved in water with varying glycerol proportions and cast as films with different degrees of plasticization. The films' electrical, dielectric, and ion transport properties were measured using electrochemical impedance spectra. The films exhibited non‐Debye character manifesting a distribution of relaxation times. The conductivity of the films increased up to 10−6 Scm−1 at 10% glycerol content. The relaxation time and diffusion coefficient values varied from 6.48 × 10−3 to 3.9110−5 s and 9.89 × 10−8 to 1.81 × 10−3 cm2s−1, respectively. The ion mobility ranged from 3.79 × 10−13 to 6.98 × 10−9 cm2v−1 s−1, and the number density ranged from 1.74 × 1021 to 1.60 × 1023 cm−3. Energy dispersive X‐ray fluorescence (EDXRF) analysis revealed the presence of several elements, primarily Ca, Ba, Na, and K. The constitution and morphology of the films were further examined using FTIR, and XRD, techniques. [ABSTRACT FROM AUTHOR]

Gamma irradiation-induced chemical decomposition and related phase transformation from SnO2 nanoparticles (NPs) to SnO have been studied using X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM) and UV–Vis spectroscopy. XRD studies show that the SnO2NPS are crystalline in nature with rutile structure. Crystallinity of the NPs increases with the increase of gamma irradiation doses, which is consistent with the results of TEM. At high gamma irradiation doses, SnO phase appears from SnO2 matrix, which pushes the SnO2 phase toward stoichiometry. The band gap energy has been found in the range of 3.84–3.76 eV, larger than the band gap of bulk SnO2. The larger band gap is attributed due to small particle size, which is confirmed by TEM studies. Optical reflectance and band gap decrease with the increase of gamma irradiation doses due to creation of defects. This property of SnO2 NPs makes it suitable for use in optical devices. [ABSTRACT FROM AUTHOR]

Successive Ionic Layer Adsorption and Reaction (SILAR) was used to deposit nanocrystalline cadmium oxide (CdO) thin films on microscopic glass substrates for various cycles (40-120). This is based on alternate dipping of the substrate in CdCl2 solution made alkaline (pH ~12) with NaOH, rinsing with distilled water, followed by air treatment with air dryer and annealing at 300 °C for 1 h in air. The prepared films were characterized by X-ray diffraction (XRD), UV-Visible Spectrophotomer (UV-Vis) and Scanning Electron Microscopy (SEM). The 80th cycle was observed to be the saturation stage for this reaction. The XRD results confirmed the films to be CdO with some Cd(OH)2 phase at higher deposition cycles. The films were polycrystalline in nature having high orientation along (111) and (200) planes. As the number of cycles increases the calculated average crystallite sizes increase gradually up till the 80th cycle after which a gradual decrease in the crystallite size was observed with increasing number of cycles. The films' transmittance in the visible and near infrared region decreased as the number of cycles increased and ranged between 25 and 80%. This work shows the feasibility of using simple SILAR method at room temperature to obtain Cd(OH)2 films which are transformed to CdO thin films after annealing. [ABSTRACT FROM AUTHOR]

The effect of annealing on the properties of chemical bath deposited (CBD) cadmium sulfide (CdS) buffer layer CuInS2 (CIS) solar cell with respect to cell performance is reported. The CdS layer was deposited on the CIS film from CdI2 and thiourea [CS(NH2)2] solutions using ammonia as the complexing agent. Results showed that post-conditional process of chemical bath deposition of CdS layer affected the performance of the CIS solar cells. X-ray diffraction (XRD) results indicated that CdS buffer layers show a hexagonal structure with preferred orientation along the (101) axis without Cd(OH)2 peak at 200°C. The morphologies of CdS films were investigated using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The performance of the CdS/CIGS solar cells was discussed on the basis of characteristics and post-deposition conditions of the chemical bath deposited CdS layer. [ABSTRACT FROM AUTHOR]

Sulfated zirconia (SZ) nanoparticles (NPs) were successfully synthesized and deposited via chemical route called sol-gel technique. The structural, morphological, and optical properties the samples were investigated by X-ray diffraction (XRD), Energy Dispersive X-ray Spectrometry (EDX), canning Electron Microscopy (SEM) and UV-visible spectrophotometer. Results show that the transmittance of the samples increased from visible region (VIS) to infrared (UV) region. It also showed that the transmittance of the samples changed with the precursor's concentrations. Furthermore, the samples showed very low absorbance which decreased toward the infrared region. The nanoparticles have wide energy bandgap that varied from 3.80 to 4.00±0.05 eV and is therefore good candidate for solar cell and solar thermal applications. It also presents an attractive alternative material for biomedical implants due to its biocompatibility and mechanical strength. [ABSTRACT FROM AUTHOR]

FexOy, thin films synthesized in the pores of PVP by chemical bath deposition techniques were deposited on glass substrates and characterized. For structural characterization, the films were subjected to x-ray diffraction (XRD), in the range of scanning angle 2θ with Cuka radiation (λ = 1.5406Å) using Philips .P.W 1500 X-ray diffractometer. The optical properties of the films were studied using absorption spectra in UV - VIS - NIR region obtained from Unico UV - 2102 PC spectrophotometer at normal incidence of light within the wavelength range 200nm - 1200nm. The synthesized FexOy films, were observed from XRD to be actually Maghemite, iron oxide, g-Fe2O3, nanocrystals of size 55.76nm; this size however decreased to 22.44nm when the precursor concentration was increased. For these films, the transmittance (42% - 97%) of radiation was high for UV-VIS-NIR regions, but the absorbance (2% - 35%) and reflectance (2% - 20%) of radiation in these regions were low. The films had low band-gap of 2.14eV for low precursor concentration, and high band-gap of 2.95eV for high precursor concentration. [ABSTRACT FROM AUTHOR]

Thin films of chromium oxide CrxOy were synthesized in the pores of PVP by chemical bath deposition technique. The effects of precursor concentration on the structural and optical properties of the films were investigated. The optical properties of the films were derived from absorbance, transmittance reflectance, refractive index and absorption coefficient measurements. Films deposited with varying precursor concentration were crystalline. The synthesized dark yellow-green CrxOy films were actually chromium oxide, Cr5O12 nanocrystals of size 12.02nm; however, as precursor concentration was increased, Cr8O21 nanocrystals of size 38.90nm were obtained. The refractive index and absorption coefficient were found to increase with increase in precursor concentration. For the same energy ranges of the incident photons, the ranges of absorption coefficient and refractive index were 0.2 - 1.7 and 1.35 - 2.35 respectively. The energy band-gap of the films ranged from 2.19eV to 2.52eV. [ABSTRACT FROM AUTHOR]

The optical properties of potash doped lead chloride (PbCl2) have been studied by sol gel technique. The optical properties of the materials were determined using a JENWAY 6405 UV-VIS spectrophotometer operating at a wavelength range of 200nm to 1200nm at an interval of 5nm. It was observed that the crystals are optically transparent. The average refractive index (n) is between 0.6 and 2.9. The refractive index greater than 2.0 makes the crystals good materials for protective coatings. The band gaps are from 3.9 to 5.0 showing that they are wide band gap materials and are good refractory materials. [ABSTRACT FROM AUTHOR]

We achieved the deposition of highly crystalline zinc oxide thin films by aqueous chemical growth process at 95oC. The precursor solution used in the deposition include Zn(NO3)2 .6H2O and C6H12 N4. Two different samples were grown on glass substrates at 5 hours and 12 hours deposition time. These were characterized by means of x-ray diffraction, scanning electron microscope, and spectrophotometer at normal incidence of light. X-ray diffraction results show that highly crystalline ZnO thin film can be achieved at a longer deposition time. Besides, the increase in the deposition time leads to a red shift in the band gap energy of the films. [ABSTRACT FROM AUTHOR]

Manganese (Mn) doped ZnO crystals have been successfully grown via the gel route. Identification of the chemical species of the crystals grown was done using Fourier Transform Infrared Spectroscopy (FTIR), structural analysis was done using X-Ray Diffraction technique while the optical properties were studied using UV-VIS technique. Results from the FTIR and XRD analysis show that high concentrations of manganese dopant ions results in the formation of synthetic MnO2 (pyrolusite), degrading the quality of the ZnO crystals. [ABSTRACT FROM AUTHOR]

CdS/CuS and CuS/CdS thin films were deposited on glass substrates at room temperature by chemical bath deposition technique. The structural characterization was done using Philips PW 1800 X-ray diffractometer (XRD) while the absorption coefficient (a) together with the band gap were determined using the absorbance and transmission measurement from a Unico uv-2102 PC spectrophotometer, at normal incidence of light in the wavelength range of 200-1000nm. The results of the optical characterization of CdS/CuS heterojunction thin films were compared with optical properties of binary thin films of CdS and CuS. The results show a clear deviation in the optical properties of the stacks of CdS/CuS thin films from the individual binary films that make up the stacks. The plot of (ah?)2 against (h?) showed that the materials have direct band gap values 1.70, 2.00, 2.10 and 2.30 eV for CuS, CuS/CdS, CdS/CuS and CdS respectively. [ABSTRACT FROM AUTHOR]

Thin films of CuSbS2 have been grown on glass substrate using the chemical bath deposition (CBD) technique at room temperature. The chemical bath for the deposition of CuSbS2 is made up of antimony chloride (SbCl3), sodium thiosulphate (Na2S2O3) and copper chloride (CuCl2). In this present work, these films were deposited at different dip time and characterized for the structural, morphological and optical properties. These properties were studied by means of X–ray diffraction (XRD), optical microscope and optical spectrophotometer for their potential application in solar energy devices. The optical properties revealed the presence of direct band gaps with energies in the 1.30 to 2.30eV range. The result shows that deposition time influences both the optical properties and band–gap energy of the films. [ABSTRACT FROM AUTHOR]

MnO2 thin films were synthesized on glass substrate by chemical bath deposition technique within the pores of polyvinyl alcohol (PVA) at room temperature. The chemical bath for the deposition of MnO2 is made up of solution of MnCl4, NH4Cl, NH3, and PVA solution. The deposited films were annealed in air at 473K and 673K and characterized for the structural, morphological and optical properties. These properties were studied by means of X-ray diffraction (XRD), optical microscopy and optical spectrophotometer for their potential application in solar energy devices. From the absorption spectra, the calculated direct and indirect band gap energies lie respectively in the range of 1.8 - 2.5 eV and 0.8 and 1.2 eV. The films show good transmittance in the near infrared region of the solar spectrum. Post deposition annealing affects both the optical and solid state properties of the films. [ABSTRACT FROM AUTHOR]

Antimony sulphide (Sb2S3) and Thallium Sulphide (Tl2S) thin films each were deposited from aqueous baths on glass substrates. Thin films of antimony sulphide (Sb2S3) were deposited from a bath containing antimony trichloride dissolved in acetone and Sodium thiosulphate. Thin films of thallium sulphide (Tl2S) were deposited from a bath containing thallium nitrate, sodium citrate, sodium hydroxide and thiourea. Some of the films produced were annealed in oven for 2hours at various temperatures. Multilayer films of Sb2S3-Tl2S and Tl2S-S2S3 were also produced, and annealed for 2hours at 180°C. The thin films produced were studied using XRD, spectrophotometer and optical microscope. From the transmittance spectra, the optical band gaps for the films were calculated. The values obtained for these materials are 1.40eV (Sb2S3), 1.30eV (Tl2S) and between 1.40 and 1.70eV for the multilayer films (Tl2S-Sb2S3). Some of the films have very poor transmittance and high absorbance values throughout the solar spectrum and therefore can be used as solar cell absorbers. [ABSTRACT FROM AUTHOR]

Thin films of Sb2S3 were deposited on glass substrates at 300 K by chemical bath deposition (CBD) technique and annealed at various temperatures. The absorption coefficient α was determined using the absorbance and transmission measurements from a Unico UV-2102 PC spectrophotometer, at normal incidence of light in the wavelength range 200-1000 nm, and the structural characterization were done using XRD and photomicrograph. The films have high absorption, greater than 90%, in the UV region but with moderate transmittance of greater than 50% for as-deposited, and poor transmittance of less than 45% for the annealed throughout the entire spectrum. Plots of (ahv)² against hv showed that the material has a direct band gap around 2.20 eV at 300 K, 1.70 eV at 453 K, and 1.60 eV at 473 K. The high absorbance of the films made them good materials for large area selective coatings for photothermal conversion of solar energy. [ABSTRACT FROM AUTHOR]

Zinc selenide (ZnSe) thin films were deposited on glass substrate using the chemical bath deposition method at room temperature from aqueous solutions of zinc sulphate and sodium selenosulfate in which sodium hydroxide was employed as complexing agents. The 'as-deposited' ZnSe thin films are red in color and annealed in oven at 473 K for 1 hour and on a hot plate in open air at 333 K for 5 minutes, affecting the morphological and optical properties. Optical properties such as absorption coefficient α and extinction coefficient k, were determined using the absorbance and transmission measurement from Unico UV-2102 PC spectrophotometer, at normal incidence of light in the wavelength range of 200-1000 nm. The films have transmittance in VIS-NIR regions that range between 26 and 87%. From absorbance and transmittance spectra, the band gap energy determined ranged between 1.60 eV and 1.75 for the 'as deposited' samples, and the annealed samples exhibited a band gap shift of 0.15 eV. The high transmittance of the films together with its large band gap made them good materials for selective coatings for solar cells. [ABSTRACT FROM AUTHOR]

Thin films of Bismuth oxyiodide (BiOI) were deposited, using chemical bath deposition techniques. The films were characterized using energy dispersive x-ray fluorescence (EDXRF) and Fourier transform infrared (FTIR) spectroscopy for chemical composition, and a spectrophotometer for the analysis of spectral absorbance / transmittance / reflectance. Deposited film thickness ranged between 0.115 and 0.140 µm. The optical properties deduced from the spectral absorbance / transmittance / reflectance include the maximum values of the refractive index n that ranged between 2.62 and 2.64, the extinction coefficient k ranged between 25.84 x 10-3 and 42.92 x 10-3 while the Optical conductivity σ ranged between 0.60 x 1014 S-1 and 0.75 x 1014 S-1. The spectral analysis revealed that some of the films grown are poor transmitters of UV but have good transmission in the VIS-NIR regions. Some of the films show transmittance above 78% in the VIS-NIR regions and a wide band gap that ranged between 3.20 and 3.40 eV. In the mid infrared regions transmittance ranged between 3 and 37%. These properties make the film potential material for poultry protection and warming coatings, solar control and antire reflection coatings and as well material for solar cell fabrication. [ABSTRACT FROM AUTHOR]

The effect of iron-doping on lead sulphide (PbS) thin films deposited on glass substrates via successive ionic layer adsorption (SILAR) Technique using lead acetate, Pb(CH3COO)2, thioacetamide (S2H5NS), Iron (II) Chloride dehydrate (FeCl2. 2H2O), ethanol and ammonia in alkaline medium annealed between 283K and 500K was investigated. The structural and morphological studies were performed by X-ray diffraction (XRD) Analysis and scanning electron microscopy (SEM) respectively. The XRD showed that PbS thin films were cubic and face-centred crystalline. [ABSTRACT FROM AUTHOR]