Abstract Excellent response with a fast response/recovery time, as well as good repeatability and longtime stability, are considered to be advantageous features of an ideal gas sensor. To this purpose, in this paper, uniform 3D flower-like layered nickel-cobalt layered double hydroxide (NiCo-LDH) composites were prepared by a simple hydrothermal method. The gas sensing performance of the NiCo-LDH NO2 gas sensors was investigated at room temperature (RT). Among the composites, Ni1Co1 (Ni/Co molar ratio = 1:1) shows a high response of 31.22 at 100 ppm with fast response and recovery times equal to 1.6 s and 11.6 s, respectively. Similarly, the Ni1Co1 sensor indicates a low detection limit of only 0.01 ppm (10 ppb) and shows excellent stability (60 days) and high selectivity to NO2. The NiCo-LDH sensor has excellent NO2 gas sensitivity performance due to its a high specific surface area or Co(OH)2 and Ni(OH)2 synergy. Therefore, we believe that Ni/Co-LDH sensors can be widely used in the field at RT and have good development prospects.

中文翻译：

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用于室温下高性能 NO2 气体传感器的 3D 花状 NiCo-LDH 复合材料

摘要 响应速度快、响应/恢复时间快、重复性好和长期稳定性好，被认为是理想气体传感器的优点。为此，本文通过简单的水热法制备了均匀的 3D 花状层状镍钴层状双氢氧化物 (NiCo-LDH) 复合材料。在室温 (RT) 下研究了 NiCo-LDH NO2 气体传感器的气体传感性能。在复合材料中，Ni1Co1（Ni/Co 摩尔比 = 1:1）在 100 ppm 下显示出 31.22 的高响应，快速响应和恢复时间分别等于 1.6 s 和 11.6 s。同样，Ni1Co1 传感器的检测下限仅为 0.01 ppm (10 ppb)，并显示出出色的稳定性（60 天）和对 NO2 的高选择性。由于其高比表面积或 Co(OH)2 和 Ni(OH)2 协同作用，NiCo-LDH 传感器具有出色的 NO2 气体灵敏度性能。因此，我们认为Ni/Co-LDH传感器可以广泛应用于RT领域，具有良好的发展前景。