Single-crystalline porous nanoplates-assembled ZnO hierarchical microstructure with superior TEA sensing properties

Abstract

Fabricating hierarchical structures has emerged as a powerful strategy to improve the gas-sensing performance of metal oxide semiconductor (MOS). In this work, we reported the synthesis of a hierarchical microstructure (HMS) of ZnO via a reliable sacrificial template method and its superior sensing performance to triethylamine (TEA). The synthesized ZnO HMS features an orderly assembly of single-crystalline porous nanoplates with the mean thickness about 27.7 nm, on which island-like nanopores are in situ created during the decomposition of Zn5(CO3)2(OH)6 sacrificial template. At the optimal working temperature (OWT) of 270 °C, the detection limit of the sensor based on ZnO HMS to TEA is as low as 50 ppb, and the sensitivity towards 50–2000 ppb TEA is as high as 20.69/ppm. Besides, the sensor also exhibits excellent selectivity, rapid response-recover rate, and good response linearity within a wide TEA concentration range from 50 ppb to 300 ppm. These characteristics make the present ZnO HMS a promising candidate for practical detection of TEA. The gas sensing mechanism was discussed in detail.