An-Najah Staff

DOI:       10.4028/www.scientific.net/AMR.1024.323

CdS thin films have been deposited onto FTO/glass substrates by two different techniques, electrochemical deposition (ECD) and chemical bath deposition (CBD). Feasibility of using these two film types in photoelectrochemical processes has been critically investigated here. The films were comparatively characterized by a number of techniques (solid state absorption spectra, solid state photoluminescence spectra, XRD and SEM). PEC characteristics of the electrodes, including current density–voltage (J–V) plots, conversion efficiency (η), stability and fill-factor (FF) were then studied. The results show that both systems involved nano-sized CdS particles living in coagulates. The ECD was thinner and more uniform than the CBD system. The CBD films were more effective in PEC processes than the ECD counterparts. Effect of annealing on characteristics of both electrode systems has been investigated. Annealing enhanced both film characteristics, but the CBD was affected to a higher extent, and the annealed CBD film was more effective than the ECD counterpart.

Tin selenide (SnSe) and copper indium diselenide (CuInSe₂) compounds were synthesized by high temperature reaction method using combination of sealed ampoule (at relatively low pressure ~10^-1 Pa without inert gas) and heating at specific temperature profile in rocking furnace. Powder X-Ray diffraction analysis reveals that the products involved only single phases of SnSe and of CuInSe₂ only. Using the reaction products as source materials, the SnSe and CuInSe₂ thin films were vacuum-deposited on glass substrates at room temperature. Structural, elemental, surface morphological and optical properties of the as-deposited films were studied by X-Ray diffraction (XRD), Energy Dispersive X-Ray (EDX) Analysis, Field Emission Scanning Electron Microscopy (FESEM) and UV-Vis-NIR spectroscopy. Single phase of SnSe and CuInSe₂ films were obtained by thermal evaporation technique from synthesized SnSe and CuInSe₂ compound without further treatment.

CdS thin films have been deposited onto FTO/glass substrates by two different techniques, electrochemical deposition (ECD) and chemical bath deposition (CBD). Feasibility of using these two film types in photoelectrochemical processes has been critically investigated here. The films were comparatively characterized by a number of techniques (solid state absorption spectra, solid state photoluminescence spectra, XRD and SEM). PEC characteristics of the electrodes, including current density–voltage (J–V) plots, conversion efficiency (η), stability and fill-factor (FF) were then studied. The results show that both systems involved nano-sized CdS particles living in coagulates. The ECD was thinner and more uniform than the CBD system. The CBD films were more effective in PEC processes than the ECD counterparts. Effect of annealing on characteristics of both electrode systems has been investigated. Annealing enhanced both film characteristics, but the CBD was affected to a higher extent, and the annealed CBD film was more effective than the ECD counterpart.

CdS thin films have been deposited onto FTO/glass substrates by two different techniques, electrochemical deposition (ECD) and chemical bath deposition (CBD). Feasibility of using these two film types in photoelectrochemical processes has been critically investigated here. The films were comparatively characterized by a number of techniques (solid state absorption spectra, solid state photoluminescence spectra, XRD and SEM). PEC characteristics of the electrodes, including current densityevoltage (JeV) plots, conversion efficiency (h), stability and fill-factor (FF) were then studied. The results show that both systems involved nano-sized CdS particles living in coagulates. The ECD was thinner and more uniform than the CBD system. The CBD films were more effective in PEC processes than the ECD counterparts. Effect of annealing on characteristics of both electrode systems has been investigated. Annealing enhanced both film characteristics, but the CBD was affected to a higher extent, and the annealed CBD film was more effective than the ECD counterpart.
2013 Published by Elsevier Masson SAS.

Bulk glasses with the chemical composition Ge_y Se_94−yIn₆ (8 ⩽ y ⩽ 30 at%) have been prepared from high purity constituent elements. Fragments of the bulk glasses are used to deposit thin films by vacuum thermal evaporation. The optical band gaps (E_g s) of the as-deposited films have been measured. The allowed optical transition is found to be indirect. The relation of E_g to the covalent coordination number, Z, is demonstrated by varying the composition parameter y of the thin films. A maximum in the compositional dependence of E_g is attained at Z = 2.63. The cohesive energies (CE) of the investigated samples have also been calculated using the method suggested by the chemical bond approach. It is found that the composition dependence of the CE also possesses a peak at Z = 2.63.A plausible explanation based on the bonding considerations between the constituents has been provided for the understanding of the E_g-Z and CE-Z dependences for these Ge–Se–In thin films.
PACS 61.43.Dq;78.66.Jg