Nanocomposite-based NH₃ gas sensors working at room temperature were systematically fabricated by compositing multi-walled carbon nanotubes (MWCNTs) and tungsten oxide (WO₃) nanobricks at different mass ratios. The response of the nanocomposite-based sensors increases with increasing WO₃ content from 0 to 95 wt% then decreases as the WO₃ content continuously increases to 100 wt%. The sensor with 95 wt% of WO₃ shows a significant enhancement in NH₃ gas sensing characteristics, namely, high response (~350% with 60 ppm NH₃), ultralow limit of detection (6 ppb), and selectivity to NH₃. The enhancement of gas sensing characteristics was attributed to the synergistic effect of the p-p junction between MWCNT and the inversion layer on the WO₃ surface caused by the adsorbed oxygen gas and water vapor in ambient air. The response increases while the sensor's resistance decreases with increasing relative humidity from 25% to 65%. Hence, MWCNT/WO₃ nanocomposite is a promising material for selective sub-ppm NH₃ gas sensor at room temperature.

通过复合不同质量比的多壁碳纳米管（MWCNT）和氧化钨（WO ₃）纳米砖，系统地制造了在室温下工作的基于纳米复合材料的NH ₃气体传感器。纳米复合材料传感器的响应随着WO ₃含量从0到95 wt％的增加而增加，然后随着WO ₃含量连续增加到100 wt％而降低。含有95 wt％WO ₃的传感器在NH ₃气敏特性方面表现出显着增强，即高响应（在60 ppm NH _3时约为350％），超低检测限（6 ppb）和对NH _3的选择性。气体感测特性的增强归因于周围空气中吸附的氧气和水蒸气引起的MWCNT与WO ₃表面上的反型层之间pp结的协同效应。当相对湿度从25％增加到65％时，响应增加，而传感器的电阻减小。因此，MWCNT / WO ₃纳米复合材料是用于室温下选择性亚ppm NH ₃气体传感器的有前途的材料。