Terahertz and infrared response assisted by heat localization in nanoporous graphene
Terahertz and infrared response assisted by heat localization in nanoporous graphene
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DOI：
10.1016/j.carbon.2020.10.059
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发表时间：
2021-03
期刊：
影响因子：
10.9
通讯作者：
D. Suzuki;T. Okamoto;Juxian Li;Yoshikazu Ito;T. Fujita;Y. Kawano
中科院分区：
文献类型：
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作者：
D. Suzuki;T. Okamoto;Juxian Li;Yoshikazu Ito;T. Fujita;Y. Kawano
在本文中，我们报告的三维双连续纳米多孔石墨烯膜的孔隙中的热捕获的直接可视化及其应用于自立，可弯曲的宽带太赫兹（THz）和红外（IR）探测器。利用散射型扫描近场光学显微镜在中红外区域，我们直接可视化，红外诱导的热是本地化的材料纳米孔的附近。纳米尺度的红外振幅图像还显示，这种热局域化效应随着孔径的减小而变得更强，并且这种行为与全局热导率和光反射的孔径依赖性一致。我们还发现，这种材料表现出高的THz和IR吸收率（>99%），同时保留了单层石墨烯的狄拉克特性;另一方面，传统石墨烯随着层数的增加而失去了这种特性。这些独特的功能使我们能够开发出一种高灵敏度，可弯曲的THz和IR检测器，由于纳米孔附近的热定位，可弯曲性和使用p-n结的高热功率，具有低热导率。因此，通过适当设计孔结构来控制热传导，这种纳米多孔石墨烯可以应用于宽带能量采集器和探测器的可穿戴热设备中。
In this paper, we report the direct visualization of heat trapping in the pores of a three-dimensional bi-continuous nanoporous graphene film and its application to a self-standing, bendable broadband terahertz (THz) and infrared (IR) detector. Utilizing a scattering-type scanning near-field optical microscope in the mid-IR region, we directly visualized that IR-induced heat is localized in the vicinities of the material nanopores. Nanoscale images of the IR amplitudes also revealed that this heat localization effect became stronger with decreasing pore diameter, and this behavior is consistent with the pore-size dependence of the global thermal conductivity and light reflection. We also found that this material exhibits a high THz and IR absorption rate (>99%), while retaining the Dirac properties of single-layer graphene; on the other hand, conventional graphene loses such properties with increasing number of layers. These unique features enabled us to develop a highly sensitive, bendable THz and IR detector with low thermal conductivity due to heat localization in the vicinities of the nanopores, bendability, and high thermopower using a p-n junction. Thus, through controlled heat conduction by the appropriate design of pore structures, this nanoporous graphene could be applied in wearable thermal devices of broadband energy harvesters and detectors.