近几年来，层状黑磷晶体材料作为一种比肩石墨烯的新型半导体材料，成为功能材料领域的研究热点，其独特的褶皱蜂窝状结构使黑磷的电学、热学等性质在层面内呈现出高度的各向异性，尽管黑磷具有高载流子迁移率，然而由于晶格热导率偏高且单层黑磷在空气中易氧化，限制了黑磷热电优值ZT的提升和在热电材料领域的应用。针对以上问题，本项目拟采用第一性原理计算方法详细研究块体黑磷和多层黑磷薄膜的电子结构、声子结构，并结合玻尔兹曼输运理论和Debye-Callaway模型研究其热电输运性质，探索黑磷薄膜的厚度和外加压力对于材料能带结构、声子结构的调制和对热电输运性质的影响；研究氮原子的掺入对于黑磷热电性能的优化机制；并利用纳米尺寸效应、掺杂和压力的协同作用调控黑磷的能带结构和声子分布，进而优化热电性能。本项目的开展为实验上制备高热电优值的黑磷材料提供了新思路，同时也为寻求其他同类结构、性能更好的热电材料提供理论借鉴。

Recently, black phosphorus (BP) has attracted much attention in the field of functional materials as it has unique properties compared to graphene. BP has a puckered layered structure which leads to significantly anisotropic electrical and thermal properties. BP has a high carrier mobility, but the lattice thermal conductivity of BP is high, and mono-layer BP is prone to oxidation in the air, which hinders the improvement of figure of merit ZT and its applications as a thermoelectric material. In this proposal, the applicant will investigate the electronic structure, phonon properties, and thermoelectric performance of bulk BP and multilayered BP thin films, using first-principles method with the combination of Boltzmann transport theory and Debye-Callaway model. The applicant will explore the effect of BP film thickness and pressure in tailoring the electronic band and phonon structures, and on thermoelectric properties of BP. Influence of nitrogen doping on thermoelectric performance of BP will also be studied. Moreover, the applicant will investigate the cooperative roles of film thickness, pressure, and doping in the modulation of band and phonon structures, and thermoelectric performance of BP will be improved accordingly. This proposal will provide new ideas for synthesizing novel high-efficiency BP materials, and also provide significantly useful information to go deep into the search of new thermoelectric materials with the similar structure and excellent properties.