A novel p–n heterojunction of an α-Fe₂O₃/NiO composite was prepared by precipitation and hydrothermal methods. The structure, morphology and composition of the composite were characterized by numerous spectroscopic methods and its gas sensing properties for triethylamine (TEA) were also tested. The results showed that the composite (Fe/Ni = 4 : 1 atomic ratio) exhibited a fast response approximately 4 times that of α-Fe₂O₃ with excellent selectivity, stability and linear response in the range from 5 to 25 ppm TEA at 140 °C, which was due to the large specific surface area of the hierarchical structure and the formation of p–n heterojunctions at the interface of both the metal oxides. Therefore, the composite synthesized in this study is a promising sensing material for the detection of TEA and the work provides a new route to rationally design sensor structures for realizing the synergetic functions of metal oxide semiconductor interfaces.

中文翻译：

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α-Fe2O3/ NiO p–n分级异质结，用于三乙胺的灵敏检测

一的α-Fe的一种新颖的p-n异质结₂ ö ₃ /氧化镍复合物通过沉淀和水热法来制备。通过多种光谱方法对复合材料的结构，形态和组成进行了表征，并测试了其对三乙胺（TEA）的气敏特性。结果表明，复合物（铁/镍= 4：1分的原子比）显示出其的快速响应的大约4倍的α-Fe ₂ ö ₃在140°C的TEA范围为5至25 ppm时具有优异的选择性，稳定性和线性响应，这是由于分层结构的大比表面积以及在两种金属的界面处形成p–n异质结氧化物。因此，本研究合成的复合材料是检测TEA的有前途的传感材料，为合理设计实现金属氧化物半导体界面协同功能的传感器结构提供了一条新途径。