The low‐temperature photoluminescence (T<300 K) and UV‐induced formation of color centers of recently synthesized Sr₂Bi₂O₅, Sr₃Bi₂O₆ and Sr₆Bi₂O₁₁ bismuthates are examined. The estimated Mott‐Seitz activation energies, ranging from 88 to 167 meV, correspond to various emission bands. Comparison of the response of all three bismuthates when exposed to UV‐illumination indicates that photoluminescence and formation of color centers are two processes that compete with photocatalytic activity. The most photoactive Sr₆Bi₂O₁₁ bismuthate exhibits neither luminescence nor the ability toward photocoloration. By contrast, Sr₂Bi₂O₅, which exhibits no photocatalytic activity, displays an intense photoluminescence; UV irradiation causes significant changes of its color. The bismuthate Sr₃Bi₂O₆ occupies an intermediate position as it exhibits some photocatalytic activity, as well as the ability to photoluminesce and to undergo photocoloration. Simple models are described to systematize the experimental results, which place these bismuthates into a new class of photoactive materials.

中文翻译：

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各种铋酸锶的光学性质：发光和紫外线诱导的光致变色

研究了最近合成的Sr ₂ Bi ₂ O ₅，Sr ₃ Bi ₂ O ₆和Sr ₆ Bi ₂ O ₁₁铋酸盐的低温光致发光（T <300 K）和UV诱导的色心形成。估计的Mott-Seitz活化能在88至167 meV之间，对应于各种发射带。比较三种铋酸盐在紫外线照射下的响应，结果表明，光致发光和色心的形成是两个与光催化活性竞争的过程。最具光敏性的Sr ₆ Bi ₂ O ₁₁铋酸盐既不发光也不呈现光致变色的能力。相反，不表现出光催化活性的Sr ₂ Bi ₂ O ₅表现出强烈的光致发光。紫外线照射会导致其颜色发生明显变化。铋酸盐Sr ₃ Bi ₂ O ₆处于中间位置，因为它具有一定的光催化活性，并且具有光致发光和光致变色的能力。描述了简单的模型来系统化实验结果，将这些铋酸盐放入一类新的光敏材料中。