Influence of the aqueous solution composition on the morphology of Zn1−xMgxO films deposited by spray pyrolysis

Abstract

Tailoring the band gap of metal oxides is an attractive property for various device applications. Zinc–magnesium-oxide (Zn_1−xMg_xO) is a sustainable material that allows control of the energy band gap through the Mg content. To reduce the deposition costs of Zn_1−xMg_xO, solution-based techniques can be employed. This study investigates spray-pyrolysis as a versatile, environment-friendly, solution-based deposition method to fabricate Zn_1−xMg_xO films with morphology and properties that strongly depend on the composition of the water-based precursor solution. Films that are either compact or covered with nanorods are obtained, with tunable amounts of incorporated Mg and corresponding band gap values. In order to show the applicability of these films, Zn_1−xMg_xO was sprayed onto transparent conducting oxide substrates that are commonly used in various devices, such as solar cells with superstrate architecture.