Cr³⁺-doped oxide phosphors attract increasing attention due to their tunable photoluminescence and versatile applications. Meanwhile, a hidden danger of toxic Cr⁶⁺-formation during the synthesis of Cr³⁺ phosphors should also be emphasized. Herein, a co-doping strategy of Bi³⁺ to spinel-typed ZnAl₂O₄:Cr³⁺ phosphor is performed and thoroughly suppresses the formation of Cr(Ⅵ). As a result, an environmentally friendly Cr⁶⁺-free Cr³⁺-activated phosphor is successfully synthesized by a one-step solid-phase method in air atmosphere. The mechanism of Cr(Ⅵ) suppression is investigated. In absence of the Cr(Ⅵ) impurity, the ZnAl₂O₄:Cr³⁺,Bi³⁺ shows an over doubled luminescence intensity than the pristine ZnAl₂O₄:Cr³⁺. This work offers an effective way to prevent Cr(Ⅵ) pollution fundamentally for the production and application of Cr³⁺ activated phosphors.

中文翻译：

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通过一步固相反应实现无 Cr6+ Cr3+ 激活尖晶石荧光粉


Cr ³⁺ 掺杂氧化物荧光粉由于其可调谐的光致发光和广泛的应用而引起越来越多的关注。同时，Cr ³⁺ 荧光粉合成过程中存在的有毒Cr ⁶⁺ 形成的隐患也值得关注。本文提出了Bi ³⁺ 与尖晶石型ZnAl ₂ O ₄ :Cr ³⁺ 荧光粉的共掺杂策略。抑制Cr(Ⅵ)的形成。结果，在空气气氛下一步固相法成功合成了一种环保型无Cr ⁶⁺ Cr ³⁺ 激活荧光粉。研究了Cr(Ⅵ)的抑制机制。在没有 Cr(Ⅵ) 杂质的情况下，ZnAl ₂ O ₄ :Cr ³⁺ ,Bi ³⁺ 显示出超过两倍的发光强度高于原始 ZnAl ₂ O ₄ :Cr ³⁺ 。该工作为Cr ³⁺ 活化荧光粉的生产和应用提供了从根本上防止Cr(Ⅵ)污染的有效途径。