In2O3-CuO NANO-FLAKES PREPARED BY SPRAY PYROLYSIS FOR GAS SENSING APPLICATION

Indium oxide: copper oxide nanoflakes deposited by spray pyrolysis using an aqueous solution of chloride powders at 1:1 indium to cupper ions ratio. XRD measurement shows polycrystalline structures of mixed In2O3 and CuO phases. The crystallinity enhanced with increasing annealing temperature and an additional ternary phase of In2Cu2O5 appeared at 623 K. AFM measurements illustrate an obvious variation in the morphology of the sample surface with the variation of annealing temperature. The SEM image shows Thin walls connected in the irregular direction created by cavities that gave the sample a high surface area. The sensing measurements against NO2 gas confirmed the best sample was that prepared at 673 K, where the sensitivity increased while the response and recovery times decreased. The optimum sensitivity appeared at 473 K operating temperature is 55%.