Temperature‐induced change in reactivity of the frequently used ionic liquid 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([C₄C₁im]BF₄) is presented as a prerequisite for the rational screening of reaction courses in material synthesis. [C₄C₁im]BF₄ becomes active with oxidic precursor compounds in reduction reaction at ϑ≥200 °C, even without the addition of an external reducing agent. The reaction mechanism of forming red amorphous selenium from SeO₂ is investigated as a model system and can be described similarly to the Riley oxidation. The reactive species but‐1‐ene, which is formed during the decomposition of [C₄C₁im]BF₄, reacts with SeO₂ and form but‐3‐en‐2‐one, water, and selenium. Elucidation of the mechanism was achieved by thermoanalytical investigations. The monotropic phase transition of selenium was analyzed by the differential scanning calorimetry. Beyond, the suitability of the single source oxide precursor Bi₂Se₃O₉ for the synthesis of Bi₂Se₃ particles was confirmed. Identification, characterization of formed solids succeeded by using light microscopy, XRD, SEM, and EDX.

中文翻译：

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离子液体的反应性：[C4C1im]BF4 从氧化物前体形成红色无定形硒和 Bi2Se3 颗粒的还原作用

温度引起的常用离子液体1-丁基-3-甲基咪唑鎓四氟硼酸盐（[C ₄ C ₁ im]BF ₄）反应活性的变化被认为是合理筛选材料合成中反应过程的先决条件。即使不添加外部还原剂，[C ₄ C ₁ im]BF _4在ϑ ≥200 °C的还原反应中也会与氧化前体化合物发生反应。_{以SeO 2}形成红色非晶态硒的反应机理作为模型系统进行了研究，并且可以类似于Riley氧化进行描述。_{[C 4} C ₁ im]BF ₄分解过程中形成的活性物质丁-1-烯与 SeO ₂反应形成丁-3-烯-2-酮、水和硒。通过热分析研究阐明了该机制。采用差示扫描量热法分析了硒的单向相变。此外，证实了单源氧化物前体Bi ₂ Se ₃ O ₉对于合成Bi ₂ Se ₃颗粒的适用性。使用光学显微镜、XRD、SEM 和 EDX 成功鉴定和表征了形成的固体。