Liu Xiaowang, Ji Qiang, Hu Qiyan, Li Chen, Chen Meiling, Sun Jian, Wang Yu, Sun Qiang, Geng Baoyou
College of Chemistry and Materials Science, The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecular-Based Materials, Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education Institutes, Centre for Nano Science and Technology , Anhui Normal University , Wuhu 241000 , P. R. China.
School of Pharmacy , Wannan Medical College , Wuhu 241002 , P. R. China.
ACS Appl Mater Interfaces. 2019 Aug 21;11(33):30146-30153. doi: 10.1021/acsami.9b09612. Epub 2019 Aug 8.
Luminescent nanoparticles with dual-mode long-lived luminescence are of great importance for their attractive applications in biosensing, bioimaging, and data encoding. Herein, we report the realization of up- and downconversion emission of Mn dopants in multilayer nanoparticles of NaGdF:Yb/Tm@NaGdF:Ce/Mn@NaYF upon excitation at 980 and 254 nm, respectively. The dual-mode emission of the Mn dopants at 531 nm have a long-lived lifetime up to ∼30 ms as a result of the spin-forbidden optical transition of Mn within the 3d configuration. After ceasing steady excitation at the two wavelengths, the long-lived feature of Mn luminescence allows a longer persistent time than lanthanide emissions, thereby enabling the ease of data decoding by a cell phone camera under a burst mode. The long-lived green upconversion emission also permits the generation of a long green tail emission upon dynamic excitation at 980 nm. These attributes make the as-prepared Mn-doped multilayer nanoparticles particularly attractive for multilevel anticounterfeiting.
具有双模式长寿命发光的发光纳米粒子因其在生物传感、生物成像和数据编码等方面的诱人应用而具有重要意义。在此，我们报道了在NaGdF:Yb/Tm@NaGdF:Ce/Mn@NaYF多层纳米粒子中，Mn掺杂剂分别在980和254 nm激发下实现上转换和下转换发射。由于Mn在3d构型内的自旋禁戒光学跃迁，Mn掺杂剂在531 nm处的双模式发射具有长达约30 ms的长寿命。在停止对这两个波长的稳定激发后，Mn发光的长寿命特性使其持续时间比镧系元素发射更长，从而能够在突发模式下通过手机相机轻松进行数据解码。长寿命的绿色上转换发射还允许在980 nm动态激发时产生长的绿色尾发射。这些特性使得所制备的Mn掺杂多层纳米粒子在多级防伪方面特别具有吸引力。
