论文标题
在二维PBSE中具有高热电性能的二维PBSE耦合
Strong interlayer coupling in two-dimensional PbSe with high thermoelectric performance
论文作者
论文摘要
通常认为，二维IV组硫化剂中相邻层之间存在弱范德华的相互作用。但是，使用PBSE作为原型示例，我们发现PB-PB层之间的其他强耦合，这通过对差分密度的详细分析证明了这一点。耦合类似于共价键，并在平衡距离周围表现出强烈的谐波，可以调节这些键，以明显降低声子导热率，但稍微改变了PBSE的电子传输。结果，对于P型系统，可以在900 K下实现最大ZT值2.5。我们的工作提供了一种有效且可行的设计策略，以增强类似分层结构的热电性能。
It was generally assumed that weak van der Waals interactions exist between neighboring layers in the two-dimensional group-IV chalcogenides. Using PbSe as a prototypal example, however, we find additional strong coupling between the Pb-Pb layers, as evidenced by detailed analysis of the differential charge density. The coupling resembles covalent-like bond and exhibits strong harmonicity around the equilibrium distance, which can be fine tuned to obviously reduce the phonon thermal conductivity but slightly change the electronic transport of PbSe. As a consequence, a maximum ZT value of 2.5 can be realized at 900 K for the p-type system. Our work offers an effective and feasible design strategy to enhance the thermoelectric performance of similar layered structures.
