High yield synthesis of intrinsic, doped and composites of nano-zinc oxide using novel combinatorial method

A novel synthesis of the production of luminescent zinc oxide (ZnO), either in its intrinsic, metal, non-metal-doped or composite forms with high yield has been developed by parallel iterative techniques, within a combinatorial library prepared by the reduction of nitroarenes. The reduction of nitroarenes by aluminium/zinc dusts in alkaline medium (pH 10 ± 2) forms azoxy compounds, whereas in acidic medium (pH 4.9 ± 0.2) forms phenyl hydroxylamine and zinc/aluminium dust gets oxidised into respective hydroxide. Here, we demonstrate the reduction of nitroarenes at neutral pH (7.0 ± 0.2), which forms intrinsic as well as doped ZnO at 50 ± 5 °C using zinc dust alone or mixtures of salts of several transition and non-transition metals in presence of 1:10 ratio of solvent and water. Interestingly, it is observed that the photoluminescence emission could be tuned in a wide range from 390 to 615. nm useful for many display related devices.