Tan Haihu, Gong Guo, Xie Shaowen, Song Ya, Zhang Changfan, Li Na, Zhang Dong, Xu Lijian, Xu Jianxiong, Zheng Jie
School of Materials Science and Energy Engineering , Foshan University , Foshan 528000 , P. R. China.
Department of Chemical and Biomolecular Engineering , The University of Akron , Akron , Ohio 44325 , United States.
Langmuir. 2019 Sep 3;35(35):11503-11511. doi: 10.1021/acs.langmuir.9b01919. Epub 2019 Aug 22.
Development of advanced fluorescent materials for constructing a secure and unclonable encryption is urgently required; however, their application in anti-counterfeiting applications is a great challenge. In this work, we proposed and synthesized a new type of upconversion nanoparticles@carbon dots@meso-SiO nanohybrids by integrating two fluorescent materials of lanthanide-doped NaYF upconversion nanoparticles (UCNPs) and carbon dots (CDs) into mesoporous silica (mSiO) to produce a novel sandwichlike core-shell structure and a dual-mode fluorescence from UCNPs and CDs. By tailoring the UCNP core of different upconversion luminescence, all three kinds of dual-mode luminescent UCNPs@CDs@mSiO nanohybrids exhibited typical RGB upconversion luminescence under a 980 nm laser and blue downconversion luminescence under a 365 nm UV light. Due to strong the hydrophilic nature of the nanohybrids, they can be further fabricated into environmentally benign luminescent inks for creating highly secured, fluorescent-based, three-dimensional anti-counterfeiting barcodes via inkjet printing. The resultant UCNPs@CDs@mSiO inks with a dual-mode and tunable luminescence nature endow the inkjet-printing barcodes with an extremely high encoding capacity and high security. Such dual-mode fluorescent inks and barcodes are simple to fabricate, easy to view, efficient for coding, and difficult to clone, thus making them promising nanomaterials for anti-counterfeiting applications.
迫切需要开发用于构建安全且不可克隆加密的先进荧光材料；然而，它们在防伪应用中的应用是一项巨大挑战。在这项工作中，我们通过将镧系掺杂的NaYF上转换纳米粒子（UCNPs）和碳点（CDs）这两种荧光材料整合到介孔二氧化硅（mSiO）中，提出并合成了一种新型的上转换纳米粒子@碳点@介孔二氧化硅纳米杂化物，以产生一种新颖的三明治状核壳结构以及来自UCNPs和CDs的双模式荧光。通过定制具有不同上转换发光的UCNP核，所有三种双模式发光的UCNPs@CDs@mSiO纳米杂化物在980 nm激光下均表现出典型的RGB上转换发光，在365 nm紫外光下表现出蓝色下转换发光。由于纳米杂化物具有很强的亲水性，它们可以进一步制成环境友好型发光墨水，通过喷墨打印来创建高度安全的、基于荧光的三维防伪条形码。所得具有双模式和可调谐发光特性的UCNPs@CDs@mSiO墨水赋予喷墨打印条形码极高的编码能力和高安全性。这种双模式荧光墨水和条形码易于制造、易于查看、编码效率高且难以克隆，因此使其成为防伪应用中有前景的纳米材料。
