Abstract A series of NiFe2O4/NiO composites composed of NiFe2O4 nanoparticles dispersing on NiO nanosheets were successfully prepared under solvothermal condition using NiO precursor and FeCl3·6H2O. Gas-sensing performance assessment demonstrated the formation of composites can improve the properties effectively. The sensor based on sample Fe/Ni-24.9 at% exhibited the optimal gas-sensing performance, showing fast response/recovery, good repeatability and high response of ~23.0 to 50 ppm acetone at 280 °C, which was about 1.8 times and 2.2 times of the pristine NiO and NiFe2O4. The excellent sensing performance can be ascribed to the p-p heterojunction between the NiO and NiFe2O4, which may decrease the charge carrier concentration in NiO near the heterojunction and bring about larger resistance variation upon the adsorption of target gas.

中文翻译：

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NiFe2O4 纳米粒子修饰的 NiO 纳米片的 pp 异质结复合材料用于丙酮气体检测

摘要 以NiO前驱体和FeCl3·6H2O为溶剂，在溶剂热条件下，成功制备了NiFe2O4纳米颗粒分散在NiO纳米片上的一系列NiFe2O4/NiO复合材料。气敏性能评估表明复合材料的形成可以有效地改善性能。基于样品 Fe/Ni-24.9 at% 的传感器表现出最佳的气敏性能，显示出快速响应/恢复、良好的重复性和高响应，在 280 °C 下约 23.0 至 50 ppm 丙酮，约为 1.8 倍和 2.2原始 NiO 和 NiFe2O4 的时间。优异的传感性能可归因于 NiO 和 NiFe2O4 之间的 pp 异质结，这可能会降低异质结附近 NiO 中的电荷载流子浓度，并在吸附目标气体时带来更大的电阻变化。