N-doped graphene (NGr) incorporated with 2H-MoS₂ and 1T-MoS₂ (NGr/2H(1T)-MoS₂) composites have been explored as anode materials for Li/K-ions batteries (LIBs/PIBs), however, the electrochemical mechanisms of their performance have not been well probed. In this work, we use first-principles calculations to investigate the atomic mechanisms associated with their high performance and cycling stability. Graphitic N (grN) is found to play a vital role in improving the structural stability of NGr/2H(1T)-MoS₂ and the electronic conductivity of NGr/2H-MoS₂, while pyridinic N and pyrrolic N are detrimental to the structural integrity of hybrids. Due to small and stable adsorption energies, fast Li⁺/K⁺ adsorption can be achieved in grNGr/2H(1T)-MoS₂ hybrids at high Li⁺/K⁺ contents. Besides, grNGr/2H(1T)-MoS₂ composites have low Li⁺/K⁺ diffusion energy barriers and large diffusion coefficients. Especially, grNGr/1T-MoS₂ displays superior Li⁺/K⁺ adsorption and diffusion capabilities as well as high electronic conductivity, making it a promising anode material for LIBs/PIBs. Based on the lattice expansion during K⁺ insertion, an optimal range of interlayer distance (6.0–6.5 Å) is found. These findings provide an in-depth understanding on the microscale Li⁺/K⁺ storage behaviour and are also instructive for optimising NGr/2H-MoS₂ composite and designing NGr/1T-MoS₂ anode material of LIBs/PIBs.

已经研究了掺有2H-MoS ₂和1T-MoS ₂（NGr / 2H（1T）-MoS ₂）复合材料的N掺杂石墨烯（NGr）作为Li / K离子电池（LIB / PIB）的负极材料，尚未对其性能的电化学机理进行深入研究。在这项工作中，我们使用第一性原理计算来研究与其高性能和循环稳定性相关的原子机制。发现石墨烯N（grN）在改善NGr / 2H（1T）-MoS ₂的结构稳定性和NGr / 2H-MoS ₂的电子电导率中起着至关重要的作用，而吡啶二氮和吡咯N对结构不利杂种的完整性。由于小的和稳定的吸附能，快的Li ⁺在高Li ⁺ / K ⁺含量的grNGr / 2H（1T）-MoS ₂杂化物中可以实现/ K ⁺吸附。此外，grNGr / 2H（1T）-MoS ₂复合材料的Li ⁺ / K ⁺扩散能垒低，扩散系数大。尤其是，grNGr / 1T-MoS ₂具有优异的Li ⁺ / K ⁺吸附和扩散能力以及高电子电导率，使其成为LIB / PIB的有前途的阳极材料。基于K ⁺期间的晶格展开插入时，可以找到最佳的层间距离范围（6.0–6.5Å）。这些发现提供了对Li ⁺ / K ⁺微观存储行为的深入了解，对于优化NGr / 2H-MoS ₂复合材料和设计LIB / PIB的NGr / 1T-MoS ₂阳极材料也具有指导意义。