Li Huashan, Grossman Jeffrey C
Department of Materials Science and Engineering Massachusetts Institute of Technology 02139 Cambridge MA USA.
Adv Sci (Weinh). 2017 Mar 31;4(8):1600467. doi: 10.1002/advs.201600467. eCollection 2017 Aug.
Control of both the regularity of a material ensemble and nanoscale architecture provides unique opportunities to develop novel thermoelectric applications based on 2D materials. As an example, the authors explore the electronic and thermal properties of functionalized graphene nanoribbons (GNRs) in the single-sheet and helical architectures using multiscale simulations. The results suggest that appropriate functionalization enables precise tuning of the doping density in a planar donor/acceptor GNR ensemble without the need to introduce an explicit dopant, which is critical to the optimization of power factor. In addition, the self-interaction between turns of a GNR may induce long-range disorder along the helical axis, which suppresses the thermal contribution from phonons with long wavelengths, leading to anomalous length independent phonon thermal transport in the quasi-1D system.
对材料集合体的规整性和纳米级结构进行控制，为基于二维材料开发新型热电应用提供了独特的机会。例如，作者使用多尺度模拟探索了单片状和螺旋状结构中功能化石墨烯纳米带（GNR）的电子和热性能。结果表明，适当的功能化能够在无需引入明确掺杂剂的情况下，精确调节平面施主/受主GNR集合体中的掺杂密度，这对功率因数的优化至关重要。此外，GNR各匝之间的自相互作用可能会沿螺旋轴诱导长程无序，从而抑制长波长声子的热贡献，导致准一维系统中与长度无关的反常声子热输运。
