MOFs-derived In2O3 hollow microtubes/ZnCo2O4 microflowers for fast and sensitive detection of n-butanol

Abstract

Metal-organic frameworks (MOFs)-derived metal oxides have a high specific surface area and porous structure, making them promising for gas sensing applications. In this paper, MOFs-derived In₂O₃/ZnCo₂O₄ composites were synthesized using a two-step solvothermal method. Through a series of characterization strategies, it is revealed that the morphology of the In₂O₃/ZnCo₂O₄ composites consists of hollow microtubes and microflowers. The gas sensing performance of In₂O₃/ZnCo₂O₄ composites was significantly enhanced compared to pure In₂O₃. Among them, the In₂O₃/ZnCo₂O₄-2 sensor exhibited superior performance towards 100 ppm n-butanol gas, with a lower operating temperature of 200℃, a higher response value of 208.7, a lower detection limit of 4.2 ppb, shorter response/recovery times of 152 s/223 s, higher selectivity, and better repeatability. Furthermore, the improved gas response can be attributed to the utilization of MOFs as self-sacrificial templates, the high specific surface area of the sensing materials, and the formation of p-n heterojunctions. This study provides a valuable reference for synthesizing n-butanol sensing materials with a high specific surface area, strong response, and excellent selectivity.