Institute of Microelectronics, Tsinghua University, Beijing 100084, China.
Nanoscale. 2012 Jun 7;4(11):3345-9. doi: 10.1039/c2nr30417a. Epub 2012 May 4.
Due to the extremely high thermal conductivity and low heat capacity per unit area of graphene, it is possible to fabricate an efficient sound-emitting device based on the thermoacoustic effect with no mechanical vibration. In this paper, the fundamental performance of this new graphene sound-emitting device (G-SED) is investigated in terms of its static behavior. The sound amplitude mapping shows that the G-SED has good sound performance under 0.01 W. The sound frequency spectra measured at different distances and angles show that the G-SED has good sound directivity. It is possible to realize sound wave manipulation by using an array of G-SEDs. The relationship between the temperature of graphene and the sound frequency was investigated by a thermal imaging instrument. The fast transient sound response in real time was recorded by applying 60 μs short time multi-pulses and single-pulse. The stable sound emission at a constant sound pressure amplitude with low noise was observed for continuous operation under a fixed frequency over several hours. Such significant performances in this G-SED indicate broad applications, and shed light on the use of graphene in the field of acoustics.
由于石墨烯极高的热导率和单位面积低热容量，有可能制造出一种基于热声效应的高效发声装置，无需机械振动。本文从静态特性方面研究了这种新型石墨烯发声器件（G-SED）的基本性能。声振幅映射表明，在 0.01 W 以下，G-SED 具有良好的发声性能。在不同距离和角度测量的声频谱表明，G-SED 具有良好的指向性。通过使用石墨烯发声器件阵列，有可能实现声波的操控。利用热成像仪研究了石墨烯的温度与声频之间的关系。通过施加 60 μs 短时间多脉冲和单脉冲，实时记录快速瞬态声响应。在固定频率下连续运行数小时，观察到在恒定声压幅度下的稳定噪声发声。G-SED 具有如此显著的性能，表明其具有广阔的应用前景，为石墨烯在声学领域的应用提供了启示。
