当前位置: X-MOL 学术J. Mater. Res. Technol. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Effect of oxidation degree on the thermal properties of graphene oxide
Journal of Materials Research and Technology ( IF 6.2 ) Pub Date : 2020-10-07 , DOI: 10.1016/j.jmrt.2020.09.092
Junjie Chen , Linke Li

The introduction of graphene oxide into both metals and polymers has yielded materials with enhanced thermal properties. Of particular interest is functionalized graphene oxide containing substantially heterogeneously distributed functional groups. The thermal properties of graphene oxide were investigated using non-equilibrium molecular dynamics to understand mechanism of thermal transport at the nanoscale. The mechanism of phonon transport in the functionalized graphene sheet was discussed, and the structure factors limiting phonon transport were determined. The results indicated that the oxidation level influences the thermal conductivity greatly. There is a need to reduce the oxidation level in order to enhance phonon transport and reduce phonon scattering in the functionalized graphene sheet. Phonon transport in the functionalized graphene sheet at a high oxidation level is governed by the phonon mean free path associated with phonon-defect scattering. Oxygen-containing functional groups adversely influence the thermal properties due to enhanced phonon-scattering arising from the increased number of phonon-scattering centers. The intrinsic thermal conductivity of about 2480 W/(m K) at room temperature agrees with existing data on single layer pristine graphene. At room temperature, the intrinsic thermal conductivity is around 72 W/(m K) at an oxidation level of 0.35 and around 670 W/(m K) at an oxidation level of 0.05. The phonon mean free path is limited mainly by interior defects and decreases with increasing the oxidation level due to enhanced phonon-defect scattering.</abstract>



中文翻译:

氧化度对氧化石墨烯热性能的影响

将氧化石墨烯引入金属和聚合物中产生了具有增强的热性能的材料。特别令人感兴趣的是包含基本上不均匀分布的官能团的官能化氧化石墨烯。使用非平衡分子动力学研究了氧化石墨烯的热性质,以了解纳米级的热传输机理。讨论了功能化石墨烯片中声子传输的机理,并确定了限制声子传输的结构因素。结果表明,氧化程度对导热系数有很大影响。需要降低氧化水平以增强声子的传输并减少功能化石墨烯片中的声子散射。高氧化水平下功能化石墨烯片中的声子传输受与声子缺陷散射相关的声子平均自由程控制。含氧官能团由于声子散射中心数目增加而引起的声子散射增强而对热性能产生不利影响。室温下的固有热导率约为2480 W /(m K)与单层原始石墨烯上的现有数据相符。在室温下,固有热导率在0.35的氧化水平下约为72 W /(m K),而在0.05的氧化水平下约为670 W /(m K)。声子平均自由程主要受内部缺陷的限制,并且由于增强的声子缺陷散射而随氧化水平的增加而减小。</ abstract>

更新日期:2020-10-07
down
wechat
bug