The assembly of thin films (TFs) having long-lasting luminescence can be expected to play an important role in the development of new-generation smart sensors, anti-counterfeiting materials, and information-encryption systems. However, such films are limited compared with their powder and solution counterparts. In this study, by exploiting the self-organization of phosphors in the two-dimensional (2D) galleries between clay nanosheets, we developed a method for the ordered assembly of long-afterglow TFs by utilizing a hydrogen-bonding layer-by-layer (LBL) process. Compared with the pristine powder, the TFs exhibit high polarization and up-conversion room-temperature phosphorescence (RTP), as well as enhanced quantum yields and luminescence lifetimes, allowing them to be used as room-temperature phosphorescent sensors for humidity and oxygen. Moreover, modified clay-based hybrids with multicolor RTP can serve as anti-counterfeiting marks and triple-mode 2D barcode displays. We anticipate that the LBL assembly process can be extended to the fabrication of other inorganic–organic room-temperature phosphorescent hybrids with smart luminescent sensor and antiforgery applications.

中文翻译：

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具有双刺激响应磷光和防伪应用的长余辉自支撑薄膜的逐层组装

可以预期具有持久发光的薄膜（TF）的组装在新一代智能传感器，防伪材料和信息加密系统的开发中将发挥重要作用。但是，与粉末和溶液对应物相比，此类膜受到限制。在这项研究中，通过利用粘土纳米片之间的二维（2D）画廊中磷光体的自组织性，我们开发了一种通过利用氢键逐层（有序）组装长余辉TF的有序组装方法（ LBL）过程。与原始粉末相比，TFs具有高极化和上转换的室温磷光（RTP），以及增强的量子产率和发光寿命，使其可用作湿度和氧气的室温磷光传感器。此外，具有多色RTP的改性粘土基杂化物可以用作防伪标记和三模式2D条码显示。我们预计，LBL组装过程可以扩展到其他具有智能发光传感器和防伪应用的无机-有机室温磷光杂化物的制造。