Electrical properties and chemiresistive response to 2,4,6 trinitrotoluene vapours of large area arrays of Ge nanowires

We study the electrical and morphological properties of random arrays of Ge nanowires (NW) deposited on sapphire substrates. NW-based devices were fabricated with the aim of developing chemiresistive-type sensors for the detection of explosive vapours. We present the results obtained on pristine and annealed NWs and, focusing on the different phenomenology observed, we discuss the critical role played by NW-NW junctions on the electrical conduction and sensing performances. A mechanism is proposed to explain the high efficiency of the annealed arrays of NWs in detecting 2,4,6 trinitrotoluene vapours. This study shows the promising potential of Ge NW-based sensors in the field of civil security.

Automated summary

In this study, we investigated the electrical and morphological properties of randomly arranged Ge nanowires on sapphire substrates. We fabricated nanowire-based devices to develop chemiresistive-type sensors for explosive vapor detection. We observed and discussed the critical role of nanowire-nanowire junctions on electrical conduction and sensing performances. Our proposed mechanism explains the high efficiency of annealed nanowire arrays in detecting 2,4,6-trinitrotoluene vapors. This study demonstrates the promising potential of Ge nanowire-based sensors in civil security.