CHARACTERIZATION OF NEW COPPER SULFIDES MATERIALS

C. Cruz-Vázquez1, R. Bernal2, M. Inoue1, y F. J. Espinoza-Beltrán3,4

1Departamento de Investigación en Polímeros y Materiales de la Universidad de Sonora ,

Rosales y Blvd. Transversal S/N, Col. Centro, Apdo. Postal 130, Hermosillo, Son., México.

2Programa de Posgrado en Física de Materiales del CICESE,

km. 107 Carretera Tijuana-Ensenada, Ensenada, B. C., México.

3Laboratorio de Investigación en Materiales del CINVESTAV-IPN, Unidad Querétaro,

Universidad Autónoma de Querétaro, Facultad de Química, Centro Universitario Cerro de las Campanas S/N, 76010 Querétaro, Qro., México.

4Centro de Investigación en Física de la Universidad de Sonora,

Apdo. Postal 5-88, 83190 Hermosillo, Sonora, México.

In previous works, we have reported that the slow reaction between a very stable copper complex, [Cu(cyclam)](ClO4)2 (cyclam: 1, 4, 8, 11-tethraazacyclotetradecane), and Na2S provides a new amorphous copper sulfide, which precipitates in the form of a dark powder, adhering a part of the compound in the form of a thin film on the walls of the reaction vessel. A CuS thin film deposited on a polyethylene substrate showed a metallic like electrical behavior down to 250 K, and was transparent in the visible region of the spectrum.

The sintetized amorphous copper sulfide resulted to be chemically active. The film was chemically modificated with iodine vapor, with alkali metal iodides and with iodine in an organic solution. In such a way, the electrical properties of the films were notoriously improved, although it was no easy to completely characterize them. Along with this, in this work we reports the characterization of the powder obtained together with the films, by using photoacoustic spectroscopy, diffuse reflectance spectroscopy, X - ray diffraction, and electrical conductivity measurements. Also the chemical treatment for the CuS powders and the characterization of the resultanting materials is reported, as an attempt to gain a major knowledge on the structure and properties of this new materials.