Thermal conductivity of confined-water in graphene nanochannels
Thermal conductivity of confined-water in graphene nanochannels
复制标题
石墨烯纳米通道中承压水的热导率
DOI：
10.1016/j.ijheatmasstransfer.2020.119502
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发表时间：
2020-05
影响因子：
5.2
通讯作者：
Runfeng Zhou
中科院分区：
文献类型：
--
作者：
Zhixiang Zhao;Chengzhen Sun;Runfeng Zhou
由于约束和附加的流固相互作用，纳米受限流体的输运性质与体相流体相比呈现出不同的特征。本文采用格林-久保公式，通过平衡分子动力学模拟计算了石墨烯纳米通道中水的导热系数。结果表明，纳米承压水的导热系数具有明显的各向异性，即垂直导热系数明显低于纵向导热系数。这种各向异性的导热系数是由于垂直方向的分子碰撞被抑制，而纵向的碰撞增强是由于水分子在石墨烯壁附近的势垒中的陷阱造成的。随着流道高度的增加，滞留水分子对垂直方向的抑制导热系数和纵向的强化导热系数的贡献均减弱，使三个方向的导热系数均接近其体积值。综上所述，我们发现了石墨烯纳米通道中承压水导热系数的各向异性和尺寸依赖性，并从热力学物理的角度揭示了其潜在的机理。
Transport properties of nano-confined fluids present distinctive characteristics comparing to the bulk fluids owing to the confinements and the additional fluid-solid interactions. Here, the thermal conductivity of water confined in the graphene nanochannels is calculated by equilibrium molecular dynamics simulations with the Green-Kubo formula. The results show that the thermal conductivity of nano-confined water is obvious anisotropic, i.e. the perpendicular thermal conductivity is obviously lower than the longitudinal thermal conductivity. This anisotropic thermal conductivity is caused by the inhibited molecular collisions in the perpendicular direction but the enhanced collisions in the longitudinal direction because of the trap of water molecules in the potential wells near the graphene walls. With increasing the channel height, the contributions of the trapped water molecules on the inhibited thermal conductivity in the perpendicular direction and the enhanced thermal conductivity in the longitudinal direction are both weakened, such that the thermal conductivity in the three directions all approach to their bulk values. In summary, the anisotropy and size-dependence of the thermal conductivity of confined water in graphene nanochannels are identified and the underlying mechanisms are revealed from the insights of thermodynamic physics.
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影响因子：
4.4
作者：
Liu, YC;Wang, Q;Zhang, L
通讯作者：
Zhang, L
DOI：
10.1021/acs.jpcb.7b10876
发表时间：
2018-01
期刊：
The journal of physical chemistry. B
影响因子：
--
作者：
Deepti Srivastava;C. Turner;E. Santiso;K. Gubbins
通讯作者：
Deepti Srivastava;C. Turner;E. Santiso;K. Gubbins
影响因子：
6.4
作者：
Chengzhen Sun;Wen-qiang Lu;B. Bai;Jie Liu
通讯作者：
Chengzhen Sun;Wen-qiang Lu;B. Bai;Jie Liu
DOI：
10.1016/j.ijheatmasstransfer.2012.05.008
发表时间：
2012-09-01
影响因子：
5.2
作者：
Giannakopoulos, A. E.;Sofos, F.;Liakopoulos, A.
通讯作者：
Liakopoulos, A.
DOI：
10.1021/acs.jpcb.8b12341
发表时间：
2019-03
期刊：
The journal of physical chemistry. B
影响因子：
--
作者：
Raja Manokaran;K. Ayappa
通讯作者：
Raja Manokaran;K. Ayappa