کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7850721 | 1508849 | 2016 | 10 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Interface-mediated extremely low thermal conductivity of graphene aerogel
ترجمه فارسی عنوان
هدایت حرارتی بسیار کم گرافیت آرژنین گرافن، رابطی است
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی انرژی
انرژی (عمومی)
چکیده انگلیسی
Due to the ultra-high thermal conductivity (κ) of graphene, graphene-based materials are expected to be good thermal conductors. Here, however, we uncovered extremely low κ of ultralight graphene aerogels (GAs). Although our GA (â¼4 mg cmâ3) is about two times heavier than air (â¼1.2 mg cmâ3), the κ (4.7 Ã 10â3â5.9 Ã 10â3 W mâ1 Kâ1) at room temperature (RT) is about 80% lower than that of air (0.0257 W mâ1 Kâ1 at 20 °C). At low temperatures, the GA's κ reaches a lower level of 2 Ã 10â4â4 Ã 10â4 W mâ1 Kâ1. This is the lowest κ ever measured to our best knowledge. The mechanism of this extremely low κ is explored by studying the temperature variation of GA's κ, thermal diffusivity (α) and specific heat (cp) from RT to as low as 10.4 K. The uncovered small, yet positive âα/âT reveals the dominant interface thermal contact resistance in thermal transport. For normal materials with thermal transport sustained by phonon-phonon scattering, âα/âT always remains negative. The study of cp suggests highly disordered and amorphous structure of GAs, which also contributes to the ultralow κ. This makes the GA a very promising thermal insulation material, especially under vacuum conditions (e.g. astronautics areas).
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Carbon - Volume 98, March 2016, Pages 381-390
Journal: Carbon - Volume 98, March 2016, Pages 381-390
نویسندگان
Yangsu Xie, Shen Xu, Zaoli Xu, Hongchao Wu, Cheng Deng, Xinwei Wang,