In this research, response of various nanostructures of cobalt ferrite including nanoparticles, nanorods and porous nanoparticles to methanol is investigated and compared. The nanostructures were prepared using a hydrothermal method and their crystallographic, morphologic and magnetic characteristics were studied by x-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM) analysis. Sensing performance of low-cost (PCB-based) sensors to methanol vapor was evaluated at different temperatures. The results showed that the sensors have the best response at low temperatures, as the optimum working temperature of cobalt ferrite nanoparticles and nanorods sensors was 90°C while the optimum performance of porous nanoparticles sensor was at room temperature (RT). The responses of sensors based on cobalt ferrite nanoparticles, porous nanoparticles and nanorods at their optimum working temperatures to 100 ppm methanol were 42.4% (90 °C), 20.26% (RT), and 13.3% (90 °C), respectively. Compared to the previous works, our proposed sensors have high responses to methanol at low temperatures. Furthermore, our sensors are repeatable, have a good stability, and can easily be recovered in air at their working temperatures.

中文翻译：

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基于钴铁氧体纳米颗粒、纳米棒和多孔纳米颗粒的低温甲醇传感器

在这项研究中，研究和比较了各种铁氧体钴纳米结构（包括纳米颗粒、纳米棒和多孔纳米颗粒）对甲醇的响应。使用水热法制备纳米结构，并通过 X 射线衍射 (XRD) 分析、扫描电子显微镜 (SEM) 和振动样品磁强计 (VSM) 分析研究了它们的晶体学、形态学和磁学特性。在不同温度下评估了低成本（基于 PCB）传感器对甲醇蒸汽的感测性能。结果表明，传感器在低温下具有最佳响应，因为钴铁氧体纳米颗粒和纳米棒传感器的最佳工作温度为 90°C，而多孔纳米颗粒传感器的最佳性能为室温 (RT)。基于钴铁氧体纳米颗粒、多孔纳米颗粒和纳米棒的传感器在其最佳工作温度下对 100 ppm 甲醇的响应分别为 42.4% (90 °C)、20.26% (RT) 和 13.3% (90 °C)。与之前的工作相比，我们提出的传感器在低温下对甲醇具有高响应。此外，我们的传感器是可重复的，具有良好的稳定性，并且可以在其工作温度下轻松地在空气中恢复。