Due to its high performance, good sensitivity, fast response and recovery time, p-n heterojunction layer-like nanostructure consisting of two kinds of semiconducting metal oxide materials can be regarded as one of the most promising sensor materials for humidity detection at room temperature. In this study, NiO–CeO p-n heterojunction-based 2D nanosheet self-assembled architectures have been developed for constructing high-performance humidity sensors. Morphology and structure characterizations reveal that the novel heterostructures are composed of 3D flower-like porous microspheres self-assembled by 2D layered nanosheets with high surface area and abundant active sites, in which the amorphous n-type CeO nanocrystalline with only several nanometers homogeneously distributes into the p-type NiO nanosheet matrix. The sensors presented excellent humidity sensing performance with high sensitivity and a pseudo-linear response to water gas in the relative wide humidity (RH) range of 11–95% at room temperature with excellent stability, reproducibility and fast response speed. These improved properties can be greatly attributed to the unique 3D flower-like architectures with a large specific surface area and the NiO–CeO heterojunction interface and synergistic effect. Such a high performances of NiO–CeO p-n heterojunction humidity sensor can have great potential applications in highly sensitive humidity sensors.

由于其高性能，良好的灵敏度，快速的响应和恢复时间，由两种半导体金属氧化物材料组成的pn异质结层状纳米结构可被视为室温下最有希望的湿度检测传感器材料之一。在这项研究中，已经开发了基于NiO–CeO pn异质结的2D纳米片自组装体系结构来构建高性能的湿度传感器。形态和结构表征表明，新颖的异质结构由3D花状多孔微球组成，这些微球由具有高表面积和丰富活性位点的2D层状纳米片自组装而成，其中只有几纳米的非晶n型CeO纳米晶体均匀地分布到其中。 p型NiO纳米片基质。这些传感器具有出色的湿度感测性能，具有很高的灵敏度，并且在室温下相对湿度（RH）在11–95％的范围内对水煤气具有伪线性响应，具有出色的稳定性，可重复性和快速的响应速度。这些改进的特性可以极大地归因于具有大比表面积的独特3D花状架构，以及NiO–CeO异质结界面和协同效应。NiO–CeO pn异质结湿度传感器的这种高性能在高灵敏度湿度传感器中具有巨大的潜在应用。这些改进的特性可以极大地归因于具有大比表面积的独特3D花状架构，以及NiO–CeO异质结界面和协同效应。NiO–CeO pn异质结湿度传感器的这种高性能在高灵敏度湿度传感器中具有巨大的潜在应用。这些改进的特性可以极大地归因于具有大比表面积的独特3D花状架构，以及NiO–CeO异质结界面和协同效应。NiO–CeO pn异质结湿度传感器的这种高性能在高灵敏度湿度传感器中具有巨大的潜在应用。