Shenghui Han,Gang Lian,Xu Zhang,Zhaozhen Cao,Qilong Wang,Deliang Cui,Ching-Ping Wong
Developing metal-free room-temperature phosphorescence (RTP) materials with ultralong lifetimes in dry and wet states simultaneously has been widely concerned due to their potential applications, which is also a tough challenge up to now. Herein, a smart construction strategy is proposed to in-situ embed boron nitride dots (BNDs) into an isogenous B 2 O 3 matrix. The BND-based materials exhibit unexpected bluish-green RTP in solid and various wet conditions (water, oxidants, organic solvents, strong acids and bases). The RTP lifetime of them in powder is as long as ~ 1.7 s, lasting over 10 s to naked eye. B 2 O 3 matrix can not only uniformly disperse the BNDs in it, but also provide a rigid environment via forming hydrogen-bonded and covalently bonded interactions between them to strongly stabilize the triplet states excitions on the dots from nonradiative deactivation. More interestingly, RTP quenching of the BND-based powder in various solutions is effectively suppressed because the B 2 O 3 matrix is not collapsed in them. For instance, the RTP lifetime in water is as long as ~ 0.9 s. Based on the distinctive RTP properties in dry and various harsh wet states, the applications of the BND-based RTP materials in multi-level anti-counterfeiting and information encryption are demonstrated.
Xu Zhang,Shenghui Han,Gang Lian,Deliang Cui,Qilong Wang
Matrix- and metal-free phosphorescence materials with long room-temperature lifetime and high-temperature phosphorescence properties have attracted tremendous attention but seldom reported. Herein, a universal fluorination strategy was proposed to obtain a series of matrix-free fluorinated boron nitride dots (F-BNDs) with markedly extended lifetime by constructing rigid F-induced hydrogen-bond networks. Miraculously, when the F-BNDs(e) were heated to 150 °C, the afterglow was temperature-controlled and still maintained with a lifetime as long as 0.25 s. In terms of their interesting phosphorescence properties, this work actually provides a guiding strategy to realize F-BND phosphorescence materials with time-resolved and temperature-controlled lifetime encoding characteristics. Widespread applications in higher-level information encryption, time-resolved information displaying, dynamic multidimensional anti-counterfeiting and colorless security ink were demonstrated.
危险品化学品经营许可证（带存储）