CoTe2量子点的制备、结构及光学性质研究(特邀)

CoTe QDs:preparation,structure and optical properties(Invited)

近年来,过渡金属碲化物(TMTs)以其独特的晶体结构和优异的物化特性引起了科学界的广泛关注和研究。本文采用超声法制备CoTe2量子点(QDs),通过TEM、AFM、EDS、XPS、XRD、FTIR等技术手段对制备的CoTe2 QDs进行了形貌和结构的表征,同时使用分光光度计(UV-Vis)、光致发光谱(PL)和光致发光激发光谱(PLE)研究了CoTe2 QDs的光学性质。结果表明,制备得到的CoTe2 QDs分散性良好、粒径均匀、呈现球形形貌,晶粒的平均直径约为3.1 nm,平均高度约为2.9 nm;CoTe2QDs在红外波段存在明显的吸收,吸收值随稀释浓度的增加而降低;当激发光波长和发射光波长依次增加时,PL和PLE峰出现红移,具有明显的Stokes位移效应,表明CoTe2 QDs的光致发光具有激发波长依赖性;CoTe2 QDs具有光致多色发光特性,不同激发光波长可发出不同颜色的光;荧光量子产率可达62.6%。CoTe2 QDs优异的光学特性尤其是在红外波段的吸收和发光特性,表明其在红外探测、激光防护涂层、荧光成像、多色发光和纳米光子器件等研究领域中具有重要的潜在应用价值,有望成为一种新型红外探测材料。

In recent years,transition metal telluride(TMTs)has attracted extensive attention and research in the scientific field due to its unique crystal structure and excellent physical and chemical properties.In this paper,CoTe2 quantum dots(QDs)was prepared by ultrasonic method,the morphology and structure of the prepared CoTe2 QDs were characterized by TEM,AFM,EDS,XPS,XRD and FTIR.The optical properties of the prepared CoTe2 QDs were investigated by Spectrophotometer(UV-Vis),Photoluminescence(PL)and Photoluminescence Excitation(PLE).CoTe2 QDs shows good dispersion,uniform particle size and spherical morphology.The average diameter and height of the grains are about 3.1 nm and 2.9 nm respectively.CoTe2 QDs shows the obvious absorption in the infrared band,and the absorption value decreases with the increase of dilution concentration.When the wavelength of excitation light and emission light increases in turn,the PL and PLE peaks have a red shift,and they have an obvious Stokes shift effect.It shows that the photoluminescence of CoTe2 QDs is wavelength dependent.CoTe2 QDs has the photoluminescence characteristic of multicolor,different excitation light wavelength can emit different colors of light.The fluorescence quantum yield of QDs is 62.6%.The excellent optical characteristics of CoTe2 QDs,especially its absorption and luminescence characteristics in the infrared band,shows that it has important potential application value in infrared detection,laser protective coating,fluorescence imaging,multicolor luminescence and nano-photonic devices,and is expected to become a new type of infrared detection material.