Accelerated crystallization of CuAlO2 delafossite phase by controlling thermal regime during solution combustion synthesis

Abstract

In the present study, for the first time, CuAlO2 delafossite phase was successfully obtained through a one-step solution combustion synthesis (SCS) process. Moreover, in order to accelerate CuAlO2 crystallization, two-step process, i.e. SCS followed by heat-treatment (different thermal regimes: continuous and discontinuous) without controlling the atmospheric oxygen, was applied. In the two-step process, heating time duration needed for the crystallization of CuAlO2 was lowered to 30 min at 1100 °C by exerting SCS on the mixture of starting materials. It was found that different thermal regimes can highly affect the formation of CuAlO2 phase. Furthermore, according to the SEM and TEM studies, it was revealed that the resultant powders have a flaky-shape morphology with lamellar structure.