Thermoelectric materials convert waste heat into electric energy. Oxyselenide-based material, specifically, p-type BiCuSeO, is one of the most promising materials for these applications. There are numerous approaches to improve the heat-to-electricity conversion performance. Usually, these approaches are applied individually, starting from the pure intrinsic material. Higher performance could, however, be reached by combining a few strategies simultaneously. In the current work, yttrium, niobium, and phosphorous substitutions on the bismuth sites in already bismuth-deficient Bi_1-xCuSeO systems were investigated via density functional theory. The bismuth-deficient system was used as the reference system for further introduction of substitutional defects. The substitution with phosphorous showed a decrease of up to 40 meV (11%) in the energy gap between conduction and valence bands at the highest substitution concentration. Doping with niobium led to the system changing from a p-type to an n-type conductor, which provides a possible route to obtain n-type BiCuSeO systems.

热电材料将废热转化为电能。基于氧硒化物的材料，特别是 p 型 BiCuSeO，是这些应用中最有前途的材料之一。有许多方法可以提高热电转换性能。通常，这些方法是单独应用的，从纯本征材料开始。然而，通过同时结合几种策略可以达到更高的性能。在目前的工作中，已经缺乏铋的 Bi _{1-x 中}铋位点上的钇、铌和磷取代通过密度泛函理论研究了 CuSeO 系统。缺铋系统被用作进一步引入替代缺陷的参考系统。在最高取代浓度下，用磷取代的导带和价带之间的能隙减少了高达 40 meV (11%)。铌掺杂导致系统从 p 型导体变为 n 型导体，这为获得 n 型 BiCuSeO 系统提供了可能的途径。