Preparation of NiO-In<sub>2</sub>O<sub>3</sub> Ordered Porous Thin Film Materials With Enhanced n-Propanol Gas Sensing Properties
Zhenyu Yuan, Jingfeng Li, Shan Luo, Haoting Zhang, Fanli Meng
Abstract
In this paper, a metal-semiconductor ordered porous film-based n-propanol gas sensor with high sensitivity, fast response and recovery was prepared by a simple self-assembly method at the gas/liquid interface. In this work, polystyrene microspheres (PSs) with a diameter of 1000 nm were selected as a self-sacrificing template, NiO and In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> as semiconductor gas-sensitive materials, and the performance of the prepared sensor was tested. The response of the pure In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> thin-film sensor to 100 ppm n-propanol gas is about 11.4 at an operating temperature of 275°C, while the modified NiO-In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> thin-film sensor can achieve an exciting response of 60 to 100 ppm of the test gas. In addition, both sensors have ultra-short response and recovery times (3s/4s for pure In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> sensors, 2s/8s for NiO-In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> sensors). The excellent sensing performance depends mainly on the special structure of the thin film material and the heterojunction formed by doping with NiO.