石墨烯/AZO/SiC复合结构的近场辐射换热特性

由于倏逝波贡献,近场辐射换热可以远超黑体辐射定律给出的极限换热热流,对近场辐射换热的调控在近场热光伏及热管理方面有重要的应用前景。石墨烯是一种有潜力的可用于近场辐射换热调控的功能材料。本文研究了由石墨烯、铝掺杂氧化锌(aluminum-doped zinc-oxide,AZO)及SiC构成的多层复合薄膜的近场辐射换热特性。研究发现:"AZO薄膜+SiC基底"结构的频谱辐射热流在SiC的SPhP频域出现谷值,而"SiC薄膜+AZO基底"结构同时在两种表面极化激元的共振频率处出现峰值;覆盖单层石墨烯薄膜对"AZO薄膜+SiC基底"结构的近场辐射换热基本没有影响;而"石墨烯/SiC薄膜/AZO基底"结构却可以同时支持三种表面极化激元,并在调控石墨烯化学势到适当值时,可以有效增强近场换热。本研究有助于理解石墨烯对近场辐射换热的调控特性。

Near-field Radiative Heat Transfer in Graphene/AZO/SiC Composite Structures

Due to the contribution of evanescent waves,the heat flux of near-field radiation can exceed that given by Stefan-Boltzmann law.So,the regulation of near-field radiative heat transfer has important application prospects in near-field thermal photovoltaic and management.Graphene is a potential functional material for the regulation of near-field radiative heat transfer.In this paper,the near-field radiative heat transfer characteristics of multilayer composite films composed of graphene,aluminum-doped zinc-oxide(AZO) and SiC are studied.It is found that the spectral radiative heat flux of the "AZO thin film+SiC substrate " structure exhibits a valley value in the SPhP frequency domain of SiC,while that of the"SiC thin film+AZO substrate" structure simultaneously peaks at the resonant frequency of the two kinds of surface polarization.The graphene film has no effect on the near-field radiative heat transfer of the "AZO film+SiC substrate" structure,while the"graphene/SiC film/AZO substrate" structure can support three kinds of surface polarization,at the same time,combining the three characteristics.Tuning the chemical potential of graphene to some appropriate values,the near-field heat transfer can be significantly enhanced.This study can help to understand the role of graphene in near-field radiative heat transfer.