Free-standing thin film electrodes hold huge promise for solid-state and micro batteries required by a range of portable electronic devices. However, for lithium-sulfur (Li–S) and lithium-metal polysulfide (Li-MS_x; M = Mo, V, Ti, etc.) batteries, the promising thin film electrodes are not possible yet because of low melting point of sulfur. Here, for the first time, we have developed amorphous molybdenum sulfide (MoS_x) – carbon (C_y) composite thin-films using a magnetron sputtering method with novel co-deposition of molybdenum metal and sulfur-carbon composite. The thin films were used as the free-standing cathode for Li-MS_x cells that demonstrates excellent cycling performance and rate capability without any shuttle effect. The Li-MoS_x cells exhibit a high areal-capacity of 115 μAh/cm² at the current density of 20 μA/cm², an excellent stability of 500 cycles and remarkable rate capability with no traces of shuttle effect. Density functional theory (DFT)-Molecular dynamics (MD) based calculations reveal the insertion of lithium via an optimal mix of conversion and intercalation reactions without breaking the base Mo-S_x structure, eliminating the shuttle effect, and producing stable cycling performance.

独立式薄膜电极为一系列便携式电子设备所需的固态和微型电池带来了巨大的希望。然而，对于锂硫 (Li-S) 和锂金属多硫化物 (Li-MS _x ; M = Mo、V、Ti等) 电池，由于其低熔点，尚未成为有前景的薄膜电极。硫。在这里，我们首次使用磁控溅射法开发了无定形硫化钼 (MoS _x ) - 碳 (C _y ) 复合薄膜，并采用钼金属和硫碳复合材料的新型共沉积。薄膜用作 Li-MS _{x 的}独立阴极电池表现出优异的循环性能和倍率能力，没有任何穿梭效应。Li-MoS _x电池在电流密度为 20 μA/cm ^{2 时}表现出 115 μAh/cm ²的高面容量、500 次循环的出色稳定性和显着的倍率性能，没有穿梭效应的痕迹。基于密度泛函理论 (DFT) - 分子动力学 (MD) 的计算揭示了锂通过转化和嵌入反应的最佳组合插入，而不会破坏基本的 Mo-S _x结构，消除穿梭效应，并产生稳定的循环性能。