Detection of NO₂ attracted increasing interest to check the air quality and monitor exhaust emission of combustion facilities. In this study, the flame spray pyrolysis (FSP) method was used to prepare the La-doped WO₃ nanoparticles as NO₂ sensing materials for the first time. The FSP-made La-doped WO₃ nanoparticles showed that the doped La atoms were dispersed homogeneously on WO₃ particles in the form of La₂O₃. It was observed that in the concentration range of 150–1200 ppb at 125$℃$, the WO₃ sensing responses were enhanced by La doping from 2.5 at% to 10 at%, and exhibited the highest sensing response when the La doping ratio was 7.5 at%. The 7.5 at% La-doped WO₃ shows the highest response (74.2) toward 900 ppb NO₂ at 125$℃$ with response/recovery times of 23 and 35 s. Then, the high-resolution XPS spectra and sensing mechanism were combined to investigate the La-doping effects, it can be found that the enhancement of La doping might result from the enriched vacancy oxygen and more absorption sites, as well as the p-n heterojunction that drives more electrons to react with NO₂. Moreover, the sensor using 7.5 at% La-doped WO₃ presented an excellent anti-interference performance to single NH₃, SO₂, CO, CO₂, and CH₄, but were disturbed by ppm-level NH₃ and SO₂ coexisted with NO₂. It also exhibited good resistance to RH fluctuation and good stability.

NO ₂的检测引起了越来越多的关注，以检查空气质量和监测燃烧设施的废气排放。本研究首次采用火焰喷射热解(FSP)方法制备了La掺杂WO ₃纳米粒子作为NO ₂传感材料。FSP制备的La掺杂WO ₃纳米颗粒表明掺杂的La原子以La ₂ O ₃的形式均匀分散在WO ₃颗粒上。据观察，在 150–1200 ppb 的浓度范围内，在 125$℃$, WO ₃传感响应从 2.5 at% 到 10 at% 的 La 掺杂增强, 当 La 掺杂率为 7.5 at% 时表现出最高的传感响应。7.5 at% La 掺杂的 WO ₃在 125 处对 900 ppb NO ₂显示出最高响应 (74.2)$℃$响应/恢复时间分别为 23 和 35 秒。然后，结合高分辨率XPS光谱和传感机制研究La掺杂效应，可以发现La掺杂的增强可能是由于空位氧和更多的吸收位点以及pn异质结的富集导致的。驱动更多的电子与 NO ₂反应。此外，使用7.5 at% La掺杂WO _{3的传感器对单一的NH 3}、SO ₂、CO、CO ₂和CH ₄表现出优异的抗干扰性能，但受到ppm级NH ₃和SO ₂共存的干扰。 NO ₂. 它还表现出良好的抗RH波动性和良好的稳定性。