research_data_may_toumiat

The data obtained in this work includes the structural and electronic properties of Cd and Zn metal monochalcogenides (MMCs) in their wurtzite structure. The lattice parameters, bandgap, band structure, and density of states were calculated using the full potential linearized augmented plane wave method (FP-LAPW) in combination with the gga_x_gam-mpw1k functional.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Fast production of ZnO nanorods by arc discharge in de-ionized water and applications in dye-sensitized solar cells

WOS:000329856800094Fast production of the ZnO nanorods by bottom up approach using arc discharge method in de-ionized water was carried out. Structural analysis showed that the obtained ZnO powder exhibits crystallize in the hexagonal wurtzite structure with (101) preferential orientation. Furthermore, transmission electron microscopy observations showed that rod-like structure is the abundant form with a bimodial grain size distribution around 10 and 30 nm. Optical characterization of the as-synthesized ZnO nanorods revealed the existence of the two absorption and photoluminescence (PL) bands both located at UV spectral region attributed to the two grain size distributions. In addition, the two additional visible bands PL spectrum located at 430 and 492 nm are attributed the interstitial zinc and oxygen vacancies; respectively. Dye sensitized solar cells (DSSCs) were successfully produced via different ruthenium based dyes and ferrocene liquid electrolyte by using of as synthesized ZnO nanorods modified photoanodes. It has been found that DSSCs made with N719 dye is the most efficient with photoconversion of approximately 7% compared to the other dyes. Such nanorod form of the ZnO nanostructures with ruthenium dyes resulted in significant improvements of the device performance in terms of electron transportation and UV light absorption. This work would explore feasible routes to synthesize efficient metal-oxide nanostructures for opto-electronic or other related applications. Published by Elsevier B. V

Effect of copper content and sulfurization process on optical, structural and electrical properties of ultrasonic spray pyrolysed Cu2ZnSnS4 thin films

This paper reports the effect of copper content and of the sulfurization process (using elemental sulfur vapor) on the growth, structure, elemental composition, and on the optical and electrical properties of Cu2ZnSnS4 (CZTS) thin films deposited on glass substrates using ultrasonic Spray Pyrolysis. For this purpose, a series of aqueous solutions consisting of copper (II) and tin (IV) chlorides, zinc (II) acetate and thiourea with different copper concentrations (x = Cu/(Zn + Sn) = 0.8, 1, 1.2 and 1.4 while Zn/Sn = 1) were prepared. X-ray diffraction, Raman spectroscopy, scanning electronic microscopy, atomic force microscopy, energy dispersive X-ray spectroscopy, ultraviolet–visible–near infrared absorbance spectroscopy and sheet resistance analyses were used to follow the evolution of the investigated properties. The results outlined a Kesterite type CZTS phase and a secondary copper sulfide (Cu2-xS) phase, and their ratio strongly depends on the copper salt concentration and heat-treatment atmosphere. No traces of secondary phases of zinc or tin sulfides are found while high purity CZTS was obtained with the post-sulfurized film at x = 1.2. It was found that the application of additional sulfurization enhances the grain growth to reach 300 nm in size and induces significant improvement of both CZTS crystallinity and electrical conductivity. The optical band gap ranges between 1.44 and 1.57 eV depending on the composition and the sulfur deficiency is strongly reduced leading to Cu-poorer and Zn-richer compounds, as compared to those annealed in nitrogen atmosphere

Effect of copper ratio and sulfurization process on optical, structural and electrical properties of ultrasonic spray pyrolysed CZTS thin films

Ultrasonic spray pyrolysed CuxZnSnS4 (CZTS) thin films with different copper ratios (x = 1.6, 2, 2.4 and 2.8) were successfully deposited on microscopic glass substrates from an aqueous solution of CuCl2 2H2O, ZnCl2, SnCl2 and thiourea. The deposited films at substrate temperature of 310 °C were heat treated up to 500 °C under N2 gas flows with and without sulfurization process (under sulfur vapor flow ). The effect of the both copper ratio and sintering atmosphere on structure, morphology, optical and electrical properties was studied by Raman scattering, AFM observations, ultraviolet-visible absorbance spectroscopy and Four Point Probe. Results showed that after sulfurization, the crystallization of samples with x=2 and 2.8 in CZTS kesterite structure is improved while the Cu- enriched film featuring larger grains in the range of 100 nm in size. The optical band gap ranges from 1.4 to 2 eV while the film with the stoichiometric composition (x=2) showed the lowest value. The sheet resistance drops significantly in all sulfurized samples and the lowest value of 131 Ohms was reached with the stoichiometric composition (x=2)