The online detection of n‐propanol concentration is required for health and safety issues in industry. Herein, through a morphology‐inherited annealing treatment of Ni/Fe bimetallic metal‐organic framework as the template, this paper reported the synthesis of porous javelin‐like NiFe₂O₄ nanorods. As gas sensing material, the ferrite showed n‐type gas‐sensing behavior as its resistance decreased in reducing gas atmospheres, and exhibited excellent n‐propanol sensing performance (the sensing response is 6.4 to 5 ppm) with ultralow detection limits (0.41 ppm) and ultrahigh gas sensitivity (1.13 ppm⁻¹) toward n‐propanol at relatively low working temperature (120 °C). Meanwhile, the sensor showed good selectivity to n‐propanol as well as excellent cyclic and long‐term stability. The unique morphology and porous structure of NiFe₂O₄ nanorods may be responsible for the excellent performance, which offer more reactive sites and accelerate the diffusion of n‐propanol gas. This facile method of preparing porous metal oxides could be extended to fabricate other gas sensing materials applied to detect other target gases.

中文翻译：

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多孔标枪样NiFe2O4纳米棒作为具有超高性能的正丙醇传感器

对于工业中的健康和安全问题，需要在线检测正丙醇浓度。本文以Ni / Fe双金属金属有机骨架为模板，通过形态学方法进行了退火处理，报道了多孔标枪样NiFe ₂ O ₄纳米棒的合成。作为气体感测材料，铁氧体表现出n型气体感测行为，因为其电阻在还原性气体气氛中会降低，并表现出出色的正丙醇感测性能（感测响应为6.4至5 ppm），且检测限极低（0.41 ppm）和超高气体敏感性（1.13 ppm ^-1）在相对较低的工作温度（120°C）下朝向正丙醇。同时，该传感器显示出对正丙醇的良好选择性以及出色的循环和长期稳定性。NiFe ₂ O ₄纳米棒的独特形态和多孔结构可能是其优异性能的原因，它提供了更多的反应位点并加速了正丙醇气体的扩散。这种制备多孔金属氧化物的简便方法可以扩展到制造用于检测其他目标气体的其他气体传感材料。