In this research, 0–1 wt% AgO_x-doped SnO₂ nanoparticles were developed based on a single-step flame spray pyrolysis process and investigated for formaldehyde (HCHO)-sensing applications. The structural evaluations by X-ray diffraction, X-ray spectroscopy, electron microscopy, nitrogen adsorption and optical absorption indicated that Ag species containing Ag⁺ and Ag²⁺ oxidation states could be embedded in 5–20 nm tetragonal SnO₂ nanoparticles as secondary AgO_x crystals, leading to smaller crystallite size, larger surface area and smaller optical bandgap. From gas-sensing measurements at 200–400 °C, AgO_x-doping with an optimal Ag content of 0.2 wt% enhanced HCHO response by more than one order of magnitude compared with that of undoped one. In particular, the 0.2 wt% AgO_x-doped SnO₂ sensing films exhibited a high response of ∼ 495 to 2000 ppm HCHO at 350 °C with high selectivity against NH₃, NO, C₂H₂, C₂H₄, H₂, CH₄, C₃H₆O, C₆H₆, C₂H₆O, CH₃OH, C₇H₈ and C₈H₁₀. Moreover, the AgO_x doped SnO₂ sensors displayed good stability and low dependencies of response on temperature and humidity. Thus, the FSP-made 0.2 wt% AgO_x-doped SnO₂ sensor could be a promising choice for selective and sensitive HCHO detections.

在这项研究中，基于单步火焰喷涂热解工艺开发了0–1 wt％掺杂AgO _x的SnO ₂纳米颗粒，并研究了其在甲醛（HCHO）感测中的应用。X射线衍射，X射线光谱，电子显微镜，氮吸附和光吸收的结构评价表明，含有Ag ⁺和Ag ²⁺氧化态的Ag物种可以作为次生AgO嵌入5-20 nm的四方SnO ₂纳米颗粒中。_x晶体，导致较小的微晶尺寸，较大的表面积和较小的光学带隙。从200–400°C的气体感测结果中，AgO _x-最佳Ag含量为0.2 wt％的掺杂与未掺杂的相比，将HCHO响应提高了一个数量级以上。尤其是，掺有0.2 wt％AgO _x的SnO ₂感测膜在350°C时对HCHO的响应高达495至2000 ppm，并且对NH ₃，NO，C ₂ H ₂，C ₂ H ₄，H具有高选择性。₂，CH ₄，C ₃ H ₆ O，C ₆ H ₆，C ₂ H ₆ O，CH ₃ OH，C ₇ H ₈和C ₈高₁₀。而且，AgO _x掺杂的SnO ₂传感器显示出良好的稳定性，并且对温度和湿度的响应依赖性低。因此，FSP制得的0.2 wt％AgO _x掺杂的SnO ₂传感器对于选择性和灵敏的HCHO检测可能是一个有前途的选择。