Effect of the Zn(II) on the reduction of Cu(II) in natural clinoptilolite

The[Cu(H2O)(n)](2+) reduction in the presence of Zn2+, with both cations supported on natural clinoptilolite, has been studied using hydrogen flow at different reduction temperatures. The analysis of the obtained results allows to conclude that the Cu2+ reduction process and the subsequent aggregation of the reduced species of copper forming particles of colloidal and nanometric size is sensitive to the presence of zinc and to the temperature of reduction. The presence of Zn2+ diminishes the temperature Of Cu2+ reduction. The Cu2+ reduction in the presence of Zn2+ could constitute an alternative procedure to control the degree of aggregation of reduced copper species and, thus, to modify the size of the resultant copper nanoparticles in the clinoptilolite matrix. (c) 2006 Elsevier B.V. All rights reserved.