Complete oxidation of isopropanol over Cu4O3 (paramelaconite) coating deposited on fiberglass by CVD

Abstract: Thin films of paramelaconite, tenorite and their mixtures were deposited on fiberglass substrate by chemical vapor deposition and catalytically evaluated by isopropanol oxidation at low temperatures between 150 and 275°C. Copper oxides were deposited using bis(2,4-pentanedionato)copper(II) as a precursor and oxygen as carrier-reactant gas. Original crystalline phases deposited on fiberglass at different temperatures or formed subsequently were characterized by several analytical techniques. Films gave crystallite sizes from 6.5 to 8.4nm and a thickness around 230nm. The fiberglass with a paramelaconite film showed a relatively high catalytic activity, more than 40%, at 250°C. Nevertheless, the fiberglass with a tenorite film exhibited a catalytic activity of only 10% at the same temperature. Above 250°C the paramelaconite experienced a notable deactivation after which the catalytic activity decreased to 6.7% at 350°C and after this, the catalyst could not be reused. This activity loss was probably due to changes in the chemical phases on fiberglass by effect of temperatures above 250°C. [Copyright &y& Elsevier]