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This paper reports the successful fabrication of glass/ZnO/CdS/CuInS2 solar cells with a superstrate structure deposited using full spray pyrolysis deposition (FSPD). The structure, and the optical and electrical properties of the constituent layers are investigated. The CuInS2 (CIS) film deposited from a starting solution with [Cu]/[In] = 1.1 and the Al-doped CuInS2 (CIAS) film deposited from a solution with [Cu]/[In] = 1.0 and [Al]/[In] = 0.12, and using a sulfurization process, is observed to exhibit the best crystallites with tetragonal structures. The optical band-gap of the CIAS film is obtained as 1.49 eV. Moreover, physical properties of both the ZnO and the CdS thin films are also studied. The obtained parameters of the cells are an open-circuit voltage of VOC = 425 mV, a short circuit current density of JSC = 14.02 mA/cm2, a fill factor of FF = 28.75%, and a conversion efficiency of η = 1.71%. The results in our experiment show that FSPD is a potential technique for preparing solar cells based on CIS absorbers in a superstrate structure with low cost and high performance.

Polycrystalline CuInS\(_{2}\) (CIS) absorber films for solar cells were prepared by spray pyrolysis of aqueuos solution of copper chloride, indium chloride and thiourea onto heated glass substrates. By optimizing the spray parameters, such as reducing/increasing the temperature of the substrate and molar ratio of Cu/In in the spraying solution, the optical characteristics of films, which are well matched to the solar spectrum, were identified. In all cases, those CIS thin films were of p-type conductivity. Transmission measurements were performed to examine the optical properties of the films; the absorption coefficient and the optical band gap of the films were calculated by transmission spectra. The absorption spectra of the films showed that this compound is a direct band gap one and its gap varied between 1.30 - 1.78 eV. Those thin films were analyzed by X-ray diffraction in order to understand the effect of layers structure on their optical properties.

Complex impedance spectroscopy (CIS) study was carried out using the 4-electrodes cell arrangement with NASICON membrane. The physical model developed in this work was based on own CIS characteristic of the system NASICON/solution, and it accurately described the experimental diagrams. The electronic parameters could be determined from the fittings with the designed model.

High power chip on board light emitting diode (HPCOBLED) are a promising solid state light technology for a variety of lighting applications. In this study, we studied temperature effect on luminous flux of HPCOBLED using VMI-PR-001 system of Vietnam Metrology Institute. The results according to the temperature Tc is increasing, luminous flux reduced. Especially HPCOBLED is larger power, decreasing luminous flux is larger. Reason of this is chance power. HPCOBLED model describes the temperature affection on luminous flux of HPCOBLED. The results of HPCOBLED model matched with that measured by the luminous flux measurement system (VMI-PR-001, Vietnam).

For the first time, hematite nanorods were successfully synthesised using iron nitrate precursors in the presence of cation SO4−2. This is also the first time that an investigation into hematite nanorods behaviour for hydrogen fuel storage has been carried out. Microspheres constructed with α-FeOOH nanorods were synthesised via a novel hydrothermal method using a mixture of Fe(NO3)3 · 4H2O and Na2SO4 as the initial material. The α-FeOOH was transformed into hematite (α-Fe2O3) nanorods through an annealing process at 600°C for 2 h. The influence of different anions on the formation of hematite α-Fe2O3 nanorods was investigated. Experimental results proved that the addition of Na2SO4 solution controlled the morphology of α-Fe2O3. Its structure and morphology were investigated using XRD, SEM and Raman techniques. The kinetic curve of hydrogen generation of some hematite morphology samples was examined by redox cycle and the hydrogen fuel was formed by oxidation with water vapour. Although the nanorod morphology of hematite samples was damaged during redox cycles, the samples demonstrated high activity for hydrogen generation in comparison with precipitation and sol gel samples. The ratio of H2/Fe of nanorod samples for two redox cycles was 1.91% and 1.76%, respectively. Thus, hematite nanorods are a promising material for storage of hydrogen fuel.