Solanki Nikhil M, Chaudhary Suresh V, Shaikh Gaushiya A, Gupta Sanjeev K, Gajjar P N
Department of Physics, University School of Sciences, Gujarat University, Ahmedabad 380 009, India.
Computational Materials and Nanoscience Group, Department of Physics, St. Xavier's College, Ahmedabad 380 009, India.
J Colloid Interface Sci. 2025 Aug 19;701:138775. doi: 10.1016/j.jcis.2025.138775.
Lithium-oxygen batteries are next-generation battery devices due to lightweight nature and high energy density with compared to conventional Li-ion batteries. These batteries consist a metal anode terminal and an oxygen diffused cathode terminal, in which oxygen is used as a reactant with metal atoms from surrounding air. Nonetheless, these systems facing the problems related to sluggish kinetics and higher overpotential due to formation of insoluble products at negative electrode during redox reaction. To address these major issues, the requirement of catalyst materials is raised to enhance the battery performance. Keep this in mind, we have investigated the potential of CrX (X = S, Se and Te) monolayer (ML) as a catalyst material for LiO batteries. Here, we systematically examined the stability and electronic properties of CrX ML using density functional theory (DFT) approach. For the dynamical and thermal stabilities, the phonon dispersion curves and ab initio molecular dynamics (AIMD) simulation were performed. All three materials exhibit outstanding conductivity and are energetically favourable for adsorption of Li atoms and O molecules. The initial nucleation process in all materials begins with the adsorption of Li metal and follows *Li➔*LiO path. Further, analysis the adsorption behaviour, structural geometries and charge distribution of LiO reaction intermediates during oxygen reduction reaction mechanism, show that CrX MLs follows four electron pathways, resulting in 2(LiO) as the final discharge product. Additionally, we have investigated the free energy for corresponding intermediates involved in both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) process. The calculated ORR and OER overpotentials are notably low: CrS (0.27 V and 0.71 V), CrSe (0.22 V and 0.71 V) and CrTe (0.17 V and 0.33 V). Our results shows that CrX MLs are serve as high performance catalyst materials to expedite the catalytic activities for LiO battery systems.
与传统锂离子电池相比，锂氧电池因其重量轻和能量密度高而成为下一代电池设备。这些电池由金属阳极终端和氧扩散阴极终端组成，其中氧与周围空气中的金属原子作为反应物。然而，由于在氧化还原反应过程中负极形成不溶性产物，这些系统面临着动力学缓慢和过电位较高的问题。为了解决这些主要问题，提高了对催化剂材料的需求以增强电池性能。牢记这一点，我们研究了CrX（X = S、Se和Te）单层（ML）作为锂氧电池催化剂材料的潜力。在此，我们使用密度泛函理论（DFT）方法系统地研究了CrX ML的稳定性和电子性质。对于动力学和热稳定性，进行了声子色散曲线和从头算分子动力学（AIMD）模拟。所有三种材料都表现出出色的导电性，并且在能量上有利于锂原子和氧分子的吸附。所有材料中的初始成核过程始于锂金属的吸附，并遵循*Li➔*LiO路径。此外，分析氧还原反应机制中LiO反应中间体的吸附行为、结构几何形状和电荷分布，表明CrX ML遵循四电子途径，最终放电产物为2(LiO)。此外，我们还研究了氧还原反应（ORR）和析氧反应（OER）过程中相应中间体的自由能。计算得到的ORR和OER过电位明显较低：CrS（0.27 V和0.71 V）、CrSe（0.22 V和0.71 V）和CrTe（0.17 V和0.33 V）。我们的结果表明，CrX ML可作为高性能催化剂材料，加速锂氧电池系统的催化活性。
