Abstract Two-dimensional (2D) materials have been proved to be very promising anode materials of many kinds of batteries, including lithium-ion batteries (LIBs). The graphene-like carbon-nitrides with lightweight nature have received intense attention. The polyaniline (C3N) multilayer has shown its capabilities in LIBs, but C3N monolayer delays its arrival at application owing to too weak lithium (Li) adsorption. In this study, for the first time, the application of C3N monolayer as anode material for LIBs is realized by introducing heteroatom doping (B, O and S) based on first-principles simulations. The O-doped C3N (ON-C3N) offers Li storage capacity of 534.42 mAh g−1, low open circuit voltage (OCV) of 0.02 V, low Li adsorption energy of −3.64 eV and single Li atom migration energy barrier of 0.78 eV. Moreover, SN-C3N can dramatically lower the migration barrier of Li (0.12 eV) with respect to that on pristine C3N (0.41 eV). Further calculations show that the Li adsorption on C3N can be enhanced and migration barrier will decrease through the application of strain. This work demonstrates that heteroatom doping coupled with strain modulation is proved to be an effective and feasible strategy for the design of high-performance carbon-based 2D anode materials of batteries.

中文翻译：

---

具有替代掺杂和应变调制的 C3N 单层用作锂离子电池的负极材料

摘要 二维（2D）材料已被证明是包括锂离子电池（LIBs）在内的多种电池的非常有前途的负极材料。具有轻质性质的类石墨烯碳氮化物受到了广泛关注。聚苯胺 (C3N) 多层已在 LIB 中显示出其能力，但由于锂 (Li) 吸附太弱，C3N 单层延迟了其应用。本研究首次基于第一性原理模拟引入杂原子掺杂（B、O和S），实现了C3N单层作为LIBs负极材料的应用。O掺杂的C3N（ON-C3N）提供534.42 mAh g-1的锂存储容量，0.02 V的低开路电压（OCV），-3.64 eV的低锂吸附能和0.78 eV的单锂原子迁移能垒. 而且，与原始 C3N (0.41 eV) 相比，SN-C3N 可以显着降低 Li (0.12 eV) 的迁移势垒。进一步的计算表明，通过施加应变，可以增强 C3N 上的锂吸附并降低迁移势垒。这项工作表明，杂原子掺杂与应变调制相结合被证明是设计高性能碳基二维电池负极材料的有效且可行的策略。