Centrosymmetric-oxide/polydimethylsiloxane elastomers emit ultra-strong non-pre-irradiation mechanoluminescence under stress and are considered one of the most ideal mechanoluminescence materials. However, previous centrosymmetric-oxide/polydimethylsiloxane elastomers show severe mechanoluminescence degradation under stretching, which limits their use in applications. Here we show an elastomer based on centrosymmetric fluoride CaF₂:Tb³⁺ and polydimethylsiloxane, with mechanoluminescence that can self-recover after each stretching. Experimentation indicates that the self-recoverable mechanoluminescence of the CaF₂:Tb³⁺/polydimethylsiloxane elastomer occurs essentially due to contact electrification arising from contact-separation interactions between the centrosymmetric phosphors and the polydimethylsiloxane. Accordingly, a contact-separation cycle model of the phosphor–polydimethylsiloxane couple is established, and first-principles calculations are performed to model state energies in the contact-separation cycle. The results reveal that the fluoride–polydimethylsiloxane couple helps to induce contact electrification and maintain the contact-separation cycle at the interface, resulting in the self-recoverable mechanoluminescence of the CaF₂:Tb³⁺/polydimethylsiloxane elastomer. Therefore, it would be a good strategy to develop self-recoverable mechanoluminescence elastomers based on centrosymmetric fluoride phosphors and polydimethylsiloxane.

中心对称氧化物/聚二甲基硅氧烷弹性体在应力作用下可发出超强的非预辐照机械发光，被认为是最理想的机械发光材料之一。然而，以前的中心对称氧化物/聚二甲基硅氧烷弹性体在拉伸下表现出严重的机械发光降解，这限制了它们的应用。在这里，我们展示了一种基于中心对称氟化物CaF ₂ :Tb ³⁺和聚二甲基硅氧烷的弹性体，其机械发光在每次拉伸后可以自我恢复。实验表明，CaF ₂ :Tb ³⁺ /聚二甲基硅氧烷弹性体的自恢复机械发光本质上是由于中心对称磷光体与聚二甲基硅氧烷之间的接触分离相互作用产生的接触带电而发生的。据此，建立了磷-聚二甲基硅氧烷对的接触-分离循环模型，并进行第一性原理计算来模拟接触-分离循环中的态能。结果表明，氟化物-聚二甲基硅氧烷对有助于诱导接触起电并维持界面处的接触分离循环，从而导致CaF ₂ :Tb ³⁺ /聚二甲基硅氧烷弹性体的自恢复机械发光。因此，开发基于中心对称氟化物荧光粉和聚二甲基硅氧烷的自恢复机械发光弹性体将是一个很好的策略。