基于磁响应光子晶体与量子点的多重变色防伪研究  

Study on Multimodal Color-switching Anti-counterfeiting Based on Magnetically Responsive Photonic Crystals and Quantum Dots

作　　者：王文涛 赵高崇 杨柳[1,2] 周意诚 丁黎明 Wang Wentao;Zhao Gaochong;Yang Liu;Zhou Yicheng;Ding Liming(School of Materials Science and Engineering,Zhejiang Sci-Tech University,Hangzhou 310018,China;Shandong Zhengchen Science and Technology Co.Ltd,Jinan 250101,China;National Center for Nanoscience and Technology,Beijing 100190,China)

机构地区：[1]浙江理工大学材料科学与工程学院,杭州310018 [2]山东正晨科技股份有限公司,济南250101 [3]国家纳米科学中心,北京100190

出　　处：《化学学报》2022年第12期1576-1582,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.21908201,22178324);浙江省自然科学基金(No.LY21B060011);中国博士后科学基金(No.2020M671793)资助

摘　　要：结合Fe_(3)O_(4)@SiO_(2)(M)超顺磁胶体粒子动态连续的磁致变色和碲化镉量子点(CdTe QDs)瞬时发射的光致发光特性,采用聚二甲基硅氧烷(PDMS)弹性体封装含有M胶体粒子和CdTe QDs的乙二醇(EG)微液滴,制得了具有多重变色功能的M/QDs/EG/PDMS复合薄膜.利用光学显微镜、光纤光谱仪、荧光光谱仪、数码相机、拉力试验机对复合薄膜的内部结构、光学性质及力学性能进行表征.结果表明,在外界磁场的诱导下,复合薄膜瞬时呈现明亮的结构色,且随着磁场强度的降低,复合薄膜的衍射波长发生连续红移,移动范围可达145 nm.此外,在紫外光的激发下,复合薄膜可呈现特定波长的荧光发射,具备良好的光致发光特性.同时,复合薄膜断裂伸长率可达132%,表现出良好的弹性,这为其附着在不同材料表面实现防伪应用提供了基础.进一步地,通过图案化设计,可制得响应变色迅速、图案隐现可逆、颜色变化多样的防伪薄膜,这有利于其在信息加密和高级别防伪领域中的应用.Counterfeiting is a growing global problem,which could be effectively curbed by developing novel anticounterfeiting materials.Responsive photonic crystals(RPCs)are one kind of promising materials for anti-counterfeiting because of their vivid rainbow effect and stimulus responsive discoloration performance.In addition to RPCs,photoluminescence materials with intrinsic emission color,can also be used for anti-counterfeiting.As one of the most common photoluminescence materials,quantum dots(QDs)exhibit narrow emission width,saturated color,and tunable emission due to the quantum confinement effect.Despite RPCs and QDs with tunable colors have shown great potential for anti-counterfeiting and information encryption,most of their color variations are actuated by a single mode,which hinders their advanced applications.In this paper,taking advantage of the dynamic continuous magnetochromic property of Fe_(3)O_(4)@SiO_(2)(M)superparamagnetic colloids in organic solvents and the photoluminescence behavior of CdTe quantum dots(CdTe QDs)under the excitation of UV light,a M/QDs/EG/PDMS composite film with multimodal color-switching function for anti-counterfeiting was fabricated by encapsulating ethylene glycol(EG)droplets containing M colloids and CdTe QDs in elastomeric polydimethylsiloxane(PDMS).The internal structure,optical and mechanical properties were characterized by optical microscope,fiber optical spectrometer,fluorescence spectrometer,digital camera and tensile testing machine.The results showed that the composite film exhibited bright structural color instantaneously under application of a magnetic field.The diffraction wavelength of the composite film displayed a continuous red or blue shift with the decrease or increase of the magnetic field intensity,and the red or blue shifting range could reach 145 nm.Moreover,the composite film could emit bright fluorescence under the excitation of UV light and exhibited good photoluminescence function.In addition,the composite film showed good elasticity and the percenta

关 键 词：超顺磁胶体粒子 量子点 磁致变色 光致发光 防伪 

分 类 号：O734[理学—晶体学] TB383.2[一般工业技术—材料科学与工程]