Morphology regulation is an effective strategy for improving the sensor sensitivity of transition metal oxide nanostructures. In this work, SnO₂ with three different morphologies (nanorods, nanoparticles, and nanopillars) has been synthesized by a simple one-step solvothermal process with the addition of various solute ratios at 180 °C for 6 h for detecting formaldehyde (HCHO) at the optimum working temperature of 320 °C. Compared to nanorods and nanopillars, the created SnO₂ nanoparticles exhibit a much faster response time and sensitivity than other samples, showing the fastest recovery time (18 s) with the highest sensitivity of 6–100 ppm of the HCHO gas. The sensing mechanism of the sensors is investigated by Brunauer–Emmett–Teller (BET) methods and X-ray photoelectron spectroscopy (XPS) analysis, revealing that the pore size distribution and amount of O_V and O_C improve the charge transfer and HCHO adsorption of nanoparticle sensors. Such an effect of morphology control on sensing performance paves an idea for the development of different structure-based HCHO sensors.

中文翻译：

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水热合成不同形貌的 SnO2 作为 HCHO 检测传感材料


形态调控是提高过渡金属氧化物纳米结构传感器灵敏度的有效策略。在这项工作中，通过简单的一步溶剂热法合成了具有三种不同形态（纳米棒、纳米颗粒和纳米柱）的 SnO ₂ ，并在 180 °C 下添加各种溶质比例 6 小时。在320℃的最佳工作温度下检测甲醛（HCHO）。与纳米棒和纳米柱相比，所创建的 SnO ₂ 纳米粒子表现出比其他样品更快的响应时间和灵敏度，表现出最快的恢复时间（18 s）和最高灵敏度为 6-100 ppm 的 HCHO气体。通过 Brunauer-Emmett-Teller (BET) 方法和 X 射线光电子能谱 (XPS) 分析研究了传感器的传感机制，揭示了 O _V 和 O _C 改善纳米颗粒传感器的电荷转移和 HCHO 吸附。形貌控制对传感性能的这种影响为开发基于不同结构的 HCHO 传感器提供了思路。