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This paper presents experimental and density functional theory (DFT) investigations of Zn doping role in the Zn@CdO ternary system. Zn doped CdO nanostructures thin films with different Zn concentrations were successfully casted on glass substrates by sol–gel spin coating method. Cubic Zn@CdO structured ternary alloyed nanostructures thin films with 0.0, 1.0, 2.0 and 3.0 wt.% Zn concentrations were obtained. An enhancement in the lateral growth of CdO cauliflower-like nanostructures was observed after Zn addition which leads to a growth of nanostructured films with improved continuity. The effect of Zn doping on the linear optical parameters such as the optical band gap, the absorption index and the refractive index were also investigated. A remarkable blue shift in the band edge was observed as Zn is incorporated into the CdO matrix. In addition, the third order nonlinear optical parameters χ(3) and n2 were calculated and found to be about 2.89 × 10–12–4.33 × 10–14 esu and 2.89 × 10–12–4.33 × 10–14 esu; respectively. A DFT based Wien2k package was utilized to theoretically investigate the lattice parameters, the electronic structure, the absorption index and the refractive index of the Zn@CdO ternary nanoalloys. The role of Zn doping on the aforesaid properties was theoretically investigated for 3.125%, 6.25%, 12.5% and 25% Zn doping concentrations and was compared with the experimentally determined parameters. The combined theoretical and experimental investigations presented herein along with the detailed discussion of the obtained findings would provide a deep understanding of the opto-electronic behavior of the Zn doped CdO nanostructured films as well as their suitability for devices applications. [ABSTRACT FROM AUTHOR]

The present work reports Cd 1-x Zn x S (x = 0.0, 1.0, 3.0 and 5.0 wt%) nanostructured thin films growth on glass substrates via spray pyrolysis technique. As grown films exhibited hexagonal wurtzite structure with preferred orientation along (002) plane. The optical band gaps of the samples were obtained in the range ∼2.41–2.45 eV. The incorporations of 5.0 wt% Zn in CdS matrix revealed a significant widening in the band gap of the films. In addition, the films nonlinear optical properties were also improved with Zn doping in the CdS system. The films optoelectronics parameters such as response, recovery time, and detectivity were measured as functions of Zn doping concentrations. The prepared films revealed a remarkable visible light photodetection that is improved with the increasing Zn doping concentrations. The optoelectronic parameters such as external quantum efficiency (EQE), detectivity (D*) and responsivity (R) were obtained and found in the order of ∼0.48–553, 1 × 109–1 × 1011 Jones and 0.15–1.72 A/W, respectively. The obtained results demonstrate the superior performance of the Cd 1-x Zn x S system and its high suitability for advanced optoelectronic applications. • High quality Cd 1-x Zn x S nanocrystalline thin films with different Zn doping concentrations grown by spray pyrolysis method. • Band gap of thin films varies significantly with Zn doping concentration in CdS matrix. • Substantial improvement shows in visible light photodetection with the increase in Zn doping concentrations. [ABSTRACT FROM AUTHOR]

Cadmium sulphide (CdS) thin films are widely used for various devices applications. Here, we report on the development of nanostructured CdS and Na-CdS thin films with enhanced optical and emission properties using an inexpensive deposition method. High quality Na-CdS nanocrystalline films were fabricated using spin coating method on glass substrates with different doping concentration (1–4 wt%). X-ray diffraction studies of the prepared films reveal a cubic zinc blende structure. The crystallites sizes of the films were found to be about ~ 5–11 nm and significantly increase with increasing Na doping concentrations. Morphological imaging of the grown films shows spherical nano-size grains in the range of 9–27 nm. The nanocrystalline films show high transmittance (~ 85%) in the visible region and was found to increase with increasing Na doping content. Room temperature photoluminescence (RTPL) spectra of the films reveal a direct band to band transition with enormous amount of enhancement in near band emission (NBE) up to 400% for the films doped with 1 and 2 wt% Na concentrations which is about ten times higher as compared with pure CdS films. A good improvement was also observed with Na doping in the linear and third order nonlinear optical properties of the films. The reported results in the current study show the high potential of Na-doped CdS films as candidates for low cost high performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

• Improved electrical stability of solvent treated PEDOT:PSS thin films is reported. • The effect of solvent treatment on the surface wetting properties of the treated PEDOT:PSS thin films was investigated. • Suggestions based on the obtained results are given for efficient device performance. Solvent post-treatment of PEDOT:PSS conductive thin films have been shown to be an effective way to improve their electrical conductivity. However, such treatment could also have an impact on the performance stability and surface properties of PEDOT:PSS films. In the current work, PEDOT:PSS samples were prepared with different thicknesses and treated using a simple solvent post-treatment method. The electrical performance stability of the solvent post-treated films was investigated over prolonged time period. The electrical stability of the studied samples shows some dependence on their thickness. Moreover, reduced electrical performance degradation was noticed after solvent treatment. An alteration in the films wetting-dewetting properties after the treatment was also observed. The correlation between the surface properties and the improved performance stability of the treated PEDOT:PSS films is discussed in the light of the obtained results. Some remarks on the impact of solvent treatment on the performance of the treated-PEDOT:PSS films based devices are also given. [ABSTRACT FROM AUTHOR]

Herein, PbI 2 nanostructured thin films were grown on glass substrates with different (0.5, 1.0 and 1.5 g) solute concentrations using a spin coating technique. The impact of the solute concentration on the structural, optical, nonlinear optical properties was examined thoroughly and was analyzed as a function of solute concentrations. The X-ray diffraction (XRD) patterns of the films confirm a hexagonal wurtzite structure with a preferred orientation along (001) plane. The band gap of the films was calculated using absorbance spectra and found to be about 2.41–2.56 eV. The refractive index (n), extinction coefficient (k), optical dielectric constant, SELF and VELF were investigated and analyzed. In addition, third order optical susceptibility (χ (3) ), nonlinear refractive index (n 2) were also calculated. The obtained data shows that the prepared films are promising for optoelectronics applications. [ABSTRACT FROM AUTHOR]

Pure CdO nanostructured thin films and Ag doped with 1.0, 2.0 and 4.0 wt% doping concentrations were fabricated successfully on glass substrates with a cost-effective spin coating technique. The prepared films exhibit a cubic crystal structure oriented along (111) plane. The surface morphology of the pure CdO films shows a cauliflower shape structure, becomes granular, and compact at high Ag doping concentration. Raman spectra of the films reveal LO (longitudinal optical) and TO (transverse optical) vibration modes at 406.80 cm−1 and 566.54 cm−1. The absorption of the films significantly varies with Ag doping concentrations and as a result, the electronic structure of the films is tailored. Moreover, the optical band gaps vary in the range of 1.42–1.70 eV. In addition, the optical parameters n, k were studied in correlation with Ag doping concentrations. The obtained room temperature photoluminescence spectra of the prepared films show a broad peak at ∼350 nm. The third order nonlinear optical parameters of the films were also examined systematically. • Cauliflower morphology of pure CdO films was observed as incorporation of Ag films morphology change drastically. • Interesting change in NBE peak was observed as incorporation of Ag in CdO films. • 4.0 wt% Ag doped CdO films reveals remarkable enhancement in third order nonlinear optical susceptibility. [ABSTRACT FROM AUTHOR]

Cd and Na co-doped ZnO nanostructured thin films with different doping concentrations were prepared using a sol-gel spin coating technique on glass substrates. The effect of doping with Cd and 1, 2 and 3 wt % Na on the structural, morphological, optical and UV detection properties of the nanostructured ZnO thin films was investigated. The grown co-doped nanostructured thin films exhibit wurtzite structure with preferential growth along the (002) plane. The change in the doping concentration was found to have a considerable effect on the grain size of the prepared films as well as their morphology. A variation in the band gap of the co-doped nanostructured thin films was also observed with changing the doping concentration. The band gap was found to vary in the range from 3.27 to 3.24 eV with increasing Na concentrations. The UV detection performance of the co-doped ZnO nanostructured thin films based UV detector was also investigated and found to strongly depend on the dopants concentrations with an obvious correlation with the variation in the films band gap. The findings of the current study show that a good control of the optical properties and the UV detection performance of the ZnO nanostructured thin films can be achieved through co-doing with Cd and Na with increased potential for their uses in high performance opto-electronic devices. • High quality ZnO nanostructured thin films co-doped with Cd and Na were prepared using sol-gel method. • The effect of co-doping with Cd and Na on the optical properties and the UV-detection performance of the films is reported. • Cd and Na co-doping significantly improves the UV detection performance of ZnO films based devices. • Co-doping with Cd & Na could be an effective route to improve the performance of ZnO based opto-electronic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • UV detection of nanostructure thin films was analyzed in correlation of grain size of films. • UV detection of nanostructure thin films was analyzed in correlation of grain size of films. • Optoelectronic performance of films considerably dependence on rpm. Here we report on the development of ZnO nanostructured thin films-based UV detectors, fabricated via cost effective sol–gel spin coating method. The prepared films possess hexagonal wurtzite structure with strong texturing along the [0 0 2] directions. Morphological studies of the films confirm the formation of nano-sized granular structures. It was found that the UV detection performance of these nanostructured films is decreased spectacularly, about thirty-fold, by reducing the grains size from 23 nm (at 1500 rpm) to about 11 nm (at 3000 rpm). The grain sizes and optical band gaps of the films were found to considerably vary with the rpm. In addition to the high UV detection performance, the prepared films show about 85–90% optical transmittance in the visible region of the solar spectrum. Our study provides a cost-effective approach for performance improvements of ZnO nanostructures based optoelectronic devices. [ABSTRACT FROM AUTHOR]