物理化学学报2024，Vol.40Issue(5)：50-53,4.DOI:10.3866/PKU.WHXB202304027
不同层数石墨烯的光热显微成像
Photothermal Microscopy of Graphene Flakes with Different Thicknesses
摘要
Abstract
Two-dimensional(2D)layered materials have attracted widespread research interest and have significantly promoted the development of chemistry,material science,and condensed matter physics.Since the emergence of graphene,2D materials with unique mechanical,thermal,optical,and electrical properties have been developed.In the case of graphene,its extraordinary mechanical strength,carrier mobility,thermal conductivity,and light-absorption over the whole spectral range in UV-Vis and near infrared guarantee a wide range of prospective applications.The electronic structure and properties of graphene flakes are dominated by their thickness,twist angle,and dielectric environment.Tailoring the interlayer interactions of graphene layers can provide additional opportunities for developing optical and electrical nanodevices,resulting in pioneering outcomes,such as the magic-angle graphene.Over the past decade,one of the most active research directions in the field of 2D materials has been the development of novel techniques that can probe the thickness-dependent physical properties of layered materials.In contrast with the intensively studied mechanical,electrical,and optical properties,microscopic investigations of the thermal characteristics of graphene flakes remain to be explored.Photothermal(PT)microscopy is a new all-optical microscopic imaging technique that has gained substantial attention and undergone long-term development in recent years,especially in the fields of nanomaterials and life sciences.The fundamental principle of PT microscopy is to heat the target sample based on the absorption of a heating beam and use a probe beam to indirectly capture information on microscale heat generation and transport.Inspired by several pioneering studies,we conducted a comparative study of the thickness-dependent PT properties of mechanically exfoliated graphene flakes in two different PT media,i.e.,air and glycerol.Whereas a nonlinear relationship between the PT intensity and sample thickness was observed in both media,the PT intensities from the two media were distinct.A high-contrast and non-monotonic PT response was observed in glycerol.The PT intensity of monolayer graphene was higher than that of bilayer graphene,and the PT intensities of graphene flakes with 2-4 layers exhibited a good linear relationship with the thickness.We also analyzed the relationship between the PT intensity and heating or probe power,demonstrating that the PT intensity as well as the absorption cross-section of graphene derived from the PT signal vary linearly with the power of both laser beams.Our study provides insights into light absorption and thermal relaxation features of graphene flakes of different thicknesses,which can guide future studies on the thermal properties of layered materials and their heterostructures.关键词
石墨烯/光热显微成像/层数依赖/光吸收/非辐射弛豫Key words
Graphene/Photothermal microscopy/Thickness-dependence/Optical absorption/Nonradiative relaxation分类
化学化工引用本文复制引用
都安邦,田玉玺,王源璠,魏志弘,张东旭,李理,杨炜青,孙千璐,赵丽丽,徐伟高..不同层数石墨烯的光热显微成像[J].物理化学学报,2024,40(5):50-53,4.基金项目
The project was supported by the National Natural Science Foundation of China(22073046,22173044,62011530133),the National Key R&D Program of China(2020YFA0406104),the Fundamental Research Funds for the Central Universities(020514380256,020514380278)and the State Key Laboratory of Analytical Chemistry for Life Science(SKLACL2217),the Natural Science Foundation of Jiangsu Province(BK20220121),Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_0096). 国家自然科学基金(22073046,22173044,62011530133),国家重点研发计划(2020YFA0406104),中央高校基本科研业务费专项资金(020514380256,020514380278),生命科学分析化学国家重点实验室(SKLACL2217),江苏省自然科学基金(BK20220121)及江苏省研究生科研与实践创新计划(KYCX22_0096)资助项目 （22073046,22173044,62011530133）
