Cadmium Acetate Solution Research Articles

Influence of F-doping on the transmittance and electron affinity of CdO thin films suitable for solar cells technology

CdO thin films were deposited by spray pyrolysis on glass substrates from a solution of cadmium acetate in water and methanol. The films are doped with fluorine by adding NH 4F to the spray solution to improve the electrooptical properties. A decrease of the transmittance for wavelengths higher than about 800 nm depending on deposition temperature and doping level is observed. The electron affinity and work function for the deposited films are determined and the effect of F-doping on these parameters is considered.

Characteristic analysis of spray deposited Cadmium oxide thin films

Thin films of cadmium oxide are prepared on a glass substrate by a spray pyrolysis technique from an aqueous solution of cadmium acetate. The X-ray diffraction studies shows that the films are polycrystalline. The room temperature resistivity is of the order of 10 −2 Ω cm. From optical absorption data the bandgap energy of CdO is estimated to be 2.5 eV. Thermoelectric power measurement is carried out to understand the conduction mechanism.

Some physical properties of F-doped CdO thin films deposited by spray pyrolysis

Transparent conducting cadmium oxide (CdO) thin films have been deposited by chemical spray pyrolysis from a solution of cadmium acetate in distilled water and methanol. The films were doped by addition of NH 4F to the solution whose optimum concentration was determined. As-deposited films show values of Hall mobility , carrier concentration, resistivity, and transmittance (at λ=825 nm) of 25.4×10 −4 m 2/Vs, 3.66×10 26 m −3, 6.72×10 −6 Ω m and 87.1% respectively. The figure of merit Φ= T 10/ R sh (3.35×10 −2 Ω −1 at 825 nm) is the highest reported in the literature for doped and undoped CdO films obtained through such an inexpensive technique.

The photochemistry of 2-halo-1-tetralones. The effect of metal(II) salts and solid supports on the nature of carbon-halogen bond cleavage

Irradiation of 2-halo-1-tetralones in a methanol solution of metal(II) salt ( e.g. copper (II) triflate, copper(II) acetate and cadmium(II) acetate) results in the formation of ionic and radicals products. The product distribution depends on the bonded halogen atom and on the salt used. The nature of the carbon-halogen bond fission in 2-halo-1-tetralones changes when the reaction is carried out in a suspension of a solid support (silica ge, silica gel impregnated with metal(II) salt).

The properties of electrophoretically deposited layers of CdS

Binderless layers of CdS up to 2 μm thick were produced by electrophoretic deposition from a sol obtained by passing H 2S through a solution of cadmium acetate. The as-deposited layers have a cubic structure and a high resistivity. Annealing in argon at 530 °C reduces the resistivity to 10 4 Ω cm and converts the layer to the hexagonal phase. When the electrophoretic layers are covered with 100 Å films of CdCl 2 and then annealed, the phase conversion proceeds rapidly at the reduced temperature of 450 °C, while the resistivity can be further reduced to 6 × 10 2 Ω cm . The electrical conductivity is limited by interparticle potential barriers which are found to be between 0.14 and 0.18 eV high. Photocapacitance studies suggest that, in addition to introducing shallow donors, substitutional chlorine is associated with a deeper donor with an ionization energy of 0.28 eV. Acceptor levels 1.0 eV above the valence band are also introduced at the same time. These are probably the acceptor components of the self-activated luminescence emission centre.

Factors affecting the efficiency of chemically deposited CdSe based photoelectrochemical cells

CdSe thin films have been deposited on titanium, nickel and stainless steel substrates by a chemical deposition technique from an aqueous solution of cadmium acetate, ammonia and sodium selenosulfate. The effects of film thickness, substrates and annealing temperature in air on the performance of CdSe based photoelectrochemical cells have been studied. Open-circuit voltages up to 728 mV have been obtained for film deposited on nickel substrates. By optimising deposition and post deposition conditions, for Ni and Ti substrates efficiencies up to 5.5% have been obtained on small (1 cm 2) cells.

Determination of sulfur in nickel-base alloys and alloy steels by isotope dilution mass spectrometry

An isotope dilution mass spectrometric method has been developed for the precise determination of 3–300 p.p.m. of sulfur in nickel-base alloys and alloy steels. The sample is dissolved in mixed acids, a spike is added, and nitrate ions are removed. Sulfate is reduced with a mixture of hydriodic, hypophosphorous, and hydrochloric acids; the hydrogen sulfide evolved is absorbed in cadmium acetate solution and converted to silver sulfide, which is burned to sulfur dioxide, for the isotope analysis. The relative standard deviation at the 50-p.p.m. level for 1-g samples is less than 3 %.

Complexometric estimation of glutamic acid by titration with standard cadmium acetate solution employing 4-(2-thiozolyl azo) resorcin

Glutamic acid can be titrated quantitatively against standard cadmium acetate using 4-(2-thiozolyl azo) resorcin as indicator in presence of boric acid-borax buffer at pH 9.0. Small concentrations of other natural amino acids do not interfere with the titration. However the presence of an equivalent molar concentration of histidine can cause an error of about 6%.

On the volumetric determination of hydrogen sulfide and soluble sulfides

Two procedures for the determination of sulfides are compared. In one, the sulfide, contained in a weakly alkaline cadmium acetate solution, is added to a neutral solution containing potassium iodide and potassium iodate, which is then acidified. It is shown that, when this order is followed, errors are introduced, which are probably due to the partial oxidation of sulfide to sulfate instead of to elemental sulfur. In the other method the sulfide in the cadmium acetate solution is added first to an acid solution, followed by the addition of the potassium iodide-iodate solution. The theoretical yield was obtained.

Rapid methods for determining different types of sulphur compounds in soil

A description is given of methods for determining quantitatively the total sulphur, oxidizable sulphur, monosulphidic sulphur, and extractable sulphur (free and organically bound) in soil. Monosulphidic sulphur is determined by boiling the soil sample with hydrochloric acid and distilling the liberated hydrogen sulphide with a nitrogen current into a cadmium acetate solution, after which the cadmium sulphide precipitate is determined iodometrically. Oxidizable sulphur is determined in a similar way by exposing the sample to tin and concentrated hydrochloric acid. Total sulphur is also determined via hydrogen sulphide, obtained in this case by ignition of the sample withferrum reductum in a nitrogen current and liberation of hydrogen sulphide with hydrochloric acid. For determining extractable sulphur, acetone is recommanded.