Morphology engineering of hierarchical spinal nickel-cobaltite nanostructures for enhanced ethanol detection

摘要: In this article, the potential of solution-processed spinel nickel-cobaltite (NiCo 2 O 4) nanostructures as chemiresistive sensors for detecting ethanol (C 2 H 5 OH) is demonstrated. Various techniques were used to characterize the structure, composition, and morphology of the as-synthesized NiCo 2 O 4 samples prior to gas sensing studies. By adjusting the reaction time, cubic crystalline NiCo 2 O 4 structures with different surface morphologies were obtained, including upright-standing nanoplatelets enclosed by nanoneedle-type structures. These nanoneedle-type structures are composed of numerous interconnected nanoparticles with diameters of∼ 4–8 nm. These unique structural and morphological characteristics enable the NiCo 2 O 4 nanostructures to exhibit excellent sensing properties towards C 2 H 5 OH gas at 140° C, with significant changes in their resistance values observed upon exposure to 10 …