Observation on Symmetry Properties of Sodium Zinc(II)-2,9,16,23-phthalocyanine Tetracarboxylate in Water:NaOH Solution

The shift of the Q-band of sodium zinc(II)-2,9,16,23-phthalocyanine tetracarboxylate (ZnPc(COONa)₄) to about 800 nm is attributed to the influence of the electron-donating property of the carboxylate groups substituted in the β–position. ZnPc(COONa)₄ which was found to have a symmetry of D _2h characterized by a splitting of the Q transition. This splitting was interpreted by the formation of dianionic symmetric ZnPc(COONa)₄ resulting from the dissociation of the pyrrole protons as well as the possibility of Na⁺ dissolution of ZnPc(COONa)₄ in the aqueous solution of NaOH.     

Physical properties of Ag-doped cadmium telluride thin films fabricated by closed-space sublimation technique

Cadmium telluride (CdTe) thin films were prepared by the closed-space sublimation (CSS) technique, using CdTe powder as evaporant onto substrates of water-white glass. In the next step, the annealed films at 450 °C for 30 min were dipped in AgNO₃–H₂O solution at room temperature. These films were again annealed at 450 °C for 1 h to obtain silver-doped samples. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), electrically i.e. DC electrical resistivity as well as photo resistivity by van der Pauw method at room temperature, dark conductivity, activation energy analysis as a function of temperature by two-probe method under vacuum, and spectrophotometry. The electron microprobe analyzer (EMPA) results showed an increase of Ag content composition in the samples by increasing the immersion time of films in solution. The Hall measurements indicated the increase in mobility and carrier concentrations of CdTe films by doping of Ag. A significant change in the shape and size of the CdTe grains were observed.     

Effect of Sodium Iodide Dopant Concentration on the Electrical Behavior of AgPO3 Glassy Networks

Physics of the Solid State - The ionic and dielectric behavior of (AgPO3)(1 – x)–NaIx (x = 0, 0.02, 0.04, …, 0.14) systems were tested in the frequency range of...     

Physical properties of ZnSe films prepared by two-source evaporation and a study of post doping effect

Two-source thermal evaporation method was utilized to prepare hard ZnSe thin films, the films were then immersed in silver nitrate solution for different time periods. The optical properties of the films were measured from the transmittance spectra. X-ray pattern of the films were also included. Final compositions of the resulting films were measured by EMPA method and comparisons between compositions by EMPA vs. optical absorbance were also reported. The dc electrical conductivity increased and a small shift in the optical band gap was also observed.