PHOTOCHEMICAL REDUCTION OF COPPER AND SILVER IONS ON CELLULOSE-CONTAINING FABRICS

Abstract

The article presents the research results on obtaining thin films of copper (II) chloride or silver nitrate on the surface of cotton fabrics. It has been demonstrated that end links contained in cellulose in the amount of a few percent are exposed to photooxidation. Photooxidation of the end links is associated with the presence of aldehyde groups, therein providing a reducing ability to cellulose. This leads to the reduction of silver nitrate and the formation of elemental silver; thus, copper (II) chloride is reduced to copper monochloride with a partial content of elemental copper. Copper monochloride is a binary semiconductor; this allows producing a surface film containing elemental copper only using additional photochemical treatment with ascorbic acid. The experiments showed that the proportion of final cellulose molecules involved in photochemical reactions was 0.98 % for the production of copper-containing films and 0.47 % for silver-containing films. From SEM images, the films contain uniformly distributed globular particles 100-600 nm in diameter.