Ex-solution process is a novel technology to grow uniformly distributed highly catalytic nanoparticles (NPs) on the surface of parent metal oxide solid support and has been recently applied to diverse engineering applications. Here, we study the effect of CoFeRu NPs which are ex-solved on the surface of Ru-doped La_0.8Sr_0.2Co_0.1Fe_0.9O_3−δ (LSCF) perovskite at reduction temperature 350–550 °C. The shape and size of decorated CoFeRu NPs on the surface of the (LSCFRu, La_0.8Sr_0.2Co_0.1Fe_0.8Ru_0.1O_3−δ) sensing layer was studied for controlled hydrogen gas sensing. The results show that the ex-solved LSCFRu sensor leads to an enhanced gas response, long-term stability, and a smaller limit of detection (LOD=0.05 ppm) against H₂ gas exposure at 450 °C. The hydrogen gas sensing properties of ex-solved LSCFRu, La_0.8Sr_0.2Co_0.1Fe_0.8Ru_0.1O_3−δ, is (R_a/R_g = 55) after reduction at 450 °C was enhanced to 20-folds compared to un-doped LSCF with a detection limit of 0.05 ppm. The high gas response is ascribed to the catalytic effect of uniformly embedded CoFeRu NPs ex-solved via p-to-n type transition of the LSCFRu parent oxide after reduction. The concept demonstrated here may serve in the development of potential ex-solved perovskite sensors for advanced and reliable hydrogen gas sensing.

中文翻译：

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用于氢气传感器的非化学计量 （La0.8Sr0.2）0.9Co0.1Fe0.8Ru0.1O3−δ 钙钛矿的 CoFeRu 固溶体纳米颗粒的原位析出溶液


防爆溶液工艺是一种在母体金属氧化物固体载体表面生长均匀分布的高催化纳米颗粒 （NPs） 的新技术，最近已应用于各种工程应用。在这里，我们研究了在还原温度 350–550 °C 下对 Ru 掺杂 La_0.8Sr_0.2Co_0.1Fe_0.9O_3−δ （LSCF） 钙钛矿表面的 CoFeRu NPs 的影响。 研究了 （LSCFRu， La_0.8Sr_0.2Co_0.1Fe_0.8Ru_0.1O_3−δ） 传感层表面装饰的 CoFeRu NPs 的形状和大小，用于受控氢气传感。结果表明，在 450 °C 下，Exsolv LSCFRu 传感器对 H₂ 气体暴露的响应增强、长期稳定性和更小的检测限 （LOD=0.05 ppm）。 在450 °C下还原后，脱溶LSCFRu、La_0.8Sr_0.2Co_0.1Fe_0.8Ru_0.1O_3−δ的氢气传感性能为（R_a/R_g = 55），与未掺杂的LSCF（检出限为0.05 ppm）相比，其氢气传感性能提高了20倍。高气体响应归因于均匀嵌入的 CoFeRu NPs 的催化作用，这些 NPs 在还原后通过 LSCFRu 母氧化物的 p-to-n 型转变进行萃取。这里展示的概念可能有助于开发潜在的 ex solve 钙钛矿传感器，以实现先进可靠的氢气传感。