摘要
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.
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.
基金
Acknowledgements This work was supported by the National Basic Research Program of China （973 Program） （No. 2014CB932103）, the National Natural Science Foundation of China （Nos. 21301016 and 21473013）, the Beijing Municipal Natural Science Foundation （No. 2152016）, and the Fundamental Research Funds for the Central Universities.
