摘要
二碲化钼(MoTe_(2))量子点具有较窄的带隙,对光的吸收覆盖可见到近红外波段,因此在红外光电探测领域有较好的应用前景。MoTe_(2)为二维层状结构,其层与层之间较弱的范德华力使得液相剥离法将MoTe_(2)体材料制备成MoTe_(2)量子点具备可行性。不同溶剂对液相剥离的影响较大,因而溶剂对剥离效果的影响是一个值得探究的问题。文中使用超声辅助的液相剥离法制备MoTe_(2)量子点,并选择六种不同的有机溶剂分别作为分散剂。在表征部分主要采用TEM分析MoTe_(2)量子点形貌和尺寸,采用XRD和XPS表征MoTe_(2)量子点的化学组成,并通过紫外-可见-近红外光谱仪与浊度计比较不同溶剂制备MoTe_(2)量子点溶液的浓度。最后,基于Hansen参数评估了不同溶剂对MoTe_(2)量子点的液相剥离效果,并探讨了其剥离机制。结果表明:NVP制备的MoTe_(2)量子点溶液浓度最大,单分散性最好;与MoTe_(2)的Hansen参数值相近的溶剂对MoTe_(2)有更好剥离效果。研究揭示了不同溶剂对MoTe_(2)量子点剥离的机制,为MoTe_(2)量子点的高效制备提供了理论支持,并有望将该方法推广至其他范德华材料的剥离制备。
Objective Molybdenum telluride(MoTe_(2)),a transition metal dichalcogenide,possesses a narrow band gap(0.9 eV)and high electron mobility,demonstrating good application prospects in infrared optoelectronics.MoTe_(2) is a two-dimensional layered crystal structure combined by van der Waals forces.It is a reliable method to prepare MoTe_(2) quantum dots and nanosheets by liquid phase exfoliation.The kinds of solvent used in the liquid phase exfoliation method play an important role in the preparation process.However,in the related reports,studies about the effect of solvents on the exfoliation effect are rare.Therefore,it is significant to explore the best solvent of liquid phase exfoliation for the preparation of MoTe_(2) quantum dots.Methods Six kinds of different solvents(1-methyl-2-pyrrolidone,1-vinyl-2-pyrrolidone,acetone,ethanol,dimethylformamide,isopropanol)were added to MoTe_(2) powder by ultrasonic-assisted liquid phase exfoliation method.The mixed solution was sonicated at 210 W ultrasonic power for 6 h,centrifuged at 3000 r/min for 10 minutes,and the supernatant was taken for comparison.The size and morphology of the six samples were observed by transmission electron microscopy.The absorbance of the quantum dot solution was measured by a UV-Vis-NIR absorption spectrometer,and the turbidity of the quantum dot solution was measured by a turbidity meter.The suitable exfoliation solvent for MoTe_(2) quantum dots was determined using Hansen solubility theory.Results and Discussions The results of transmission electron microscopy(Fig.2)show that the quantum dots prepared by 1-vinyl-2-pyrrolidone solution have the smallest size and the most uniform particle size.From the data of FTIR spectra and XRD patterns(Fig.3),it is known that the composition of quantum dots does not change during the ultrasonic process.The Hansen parameter diagram(Fig.6)shows that 1-vinyl-2-pyrrolidone with the smallest Ra value becomes a more suitable exfoliation solvent in theory.Combined with the statistical data and calculation results of(Tab.1)and(Tab.2),it is confirmed that 1-vinyl-2-pyrrolidone is indeed the suitable exfoliation solvent for MoTe_(2).Conclusions By comparing the liquid phase exfoliation effect of six kinds of solvents for MoTe_(2),it was found that the choice of solvent directly affects the liquid phase exfoliation effect.Combined with the calculation results of Hansen solubility theory and the experimental results of turbidity method,it was concluded that 1-vinyl-2-pyrrolidone solvent was more suitable for liquid phase exfoliation of MoTe_(2).
作者
李国彬
张泰玮
胡坤
杨奥
夏溢坪
李学铭
唐利斌
杨培志
陈晟迪
杨丽
张艳
LI Guobin;ZHANG Taiwei;HU Kun;YANG Ao;XIA Yiping;LI Xueming;TANG Libin;YANG Peizhi;CHEN Shengdi;YANG Li;ZHANG Yan(Key Laboratory of Advanced Technique&Preparation for Renewable Energy Materials,Ministry of Education,School of Energy and Environmental Sciences,Yunnan Normal University,Kunming 650500,China;Kunming Institute of Physics,Kunming 650223,China;Yunnan Key Laboratory of Advanced Photoelectric Materials&Devices,Kunming 650223,China)
出处
《红外与激光工程》
北大核心
2025年第7期101-109,共9页
Infrared and Laser Engineering
基金
国家重点研发计划项目(2019YFB2203404)
云南省科技厅科技人才与平台计划项目(202205AC160026)
云南省创新团队项目(2018HC020)。
关键词
二碲化钼
量子点
液相剥离法
Hansen参数
molybdenum ditelluride
quantum dots
liquid phase exfoliation
Hansen parameter
