Ppb-Level Detection Triethylamine Gas Sensor Based on Ag-Doped Nanosheets-Assembled Octahedron Zn2SnO4

Abstract

The current semiconductor sensors cannot detect the ultra-low concentration of triethylamine (TEA). Therefore, this paper uses the catalytic activation effect of precious metal silver and combined with the unique physical and chemical properties of ternary metal oxides to design the Ag-doped Zn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> SnO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> gas sensor to detect the ultra-low concentration of TEA. In this work, spinel-type metal oxides Zn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> SnO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> was prepared by one-step hydrothermal method and its functional modification by means of precious metal doping. The countenance and elemental content of the synthesized products were dissected through diverse means. Combined with the characterization data, it is shown that Zn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> SnO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> samples all present a fixed octahedral shape and the surface is assembled by a large number of nanoplates. The gas sensing test results show that the gas sensor based on 3at% (atom percent) Ag doped Zn <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> SnO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> has the best gas sensing performance for TEA. Its response to 100 ppm TEA at 250°C is 273.33. At the same time, the minimum detectable concentration level is 100 ppb. In addition, the material also demonstrates fast response time, good stability and high selectivity. The excellent gas sensing performance is mainly attributed to the synergistic effect of chemical sensitization and electron sensitization of precious metal silver.