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Molybdenum disulfide (MoS2), a typical two-dimensional transition metallic layered material, attracts tremendous attentions in the electrochemical energy storage due to its excellent physicochemical properties. However, with the deepening of the research and exploration of the lithium storage mechanism of these advanced MoS2-based anode materials, the complex reaction process influenced by internal and external factors hinders the exhaustive understanding of the lithium storage process. To design stable anode material with high performance, it is urgent to review the mechanisms of reported anode materials and summarize the related factors that influence the reaction processes. This review aims to dissect all possible side reactions during charging and discharging process, uncover internal and external factors inducing various anode reactions and finally put forward strategies of controlling high cycling capacity and super-stable lithium storage capability of MoS2. This review will be helpful to the design of MoS2-based lithium-ion batteries (LIBs) with excellent cycle performance to enlarge the application fields of these advanced electrochemical energy storage devices.

Molybdenum disulfide (MoS2) with low cost, high activity and high earth abundance has been found to be a promising catalyst for the hydrogen evolution reaction (HER), but its catalytic activity is considerably limited due to its inert basal planes. Here, through the combination of theory and experiment, we propose that doping Ni in MoS2 as catalyst can make it have excellent catalytic activity in different reaction systems. In the EY/TEOA system, the maximum hydrogen production rate of EY/Ni-Mo-S is 2.72 times higher than that of pure EY, which confirms the strong hydrogen evolution activity of Ni-Mo-S nanosheets as catalysts. In the lactic acid and Na2S/Na2SO3 systems, when Ni-Mo-S is used as co-catalyst to compound with ZnIn2S4 (termed as Ni-Mo-S/ZnIn2S4), the maximum hydrogen evolution rates in the two systems are 5.28 and 2.33 times higher than those of pure ZnIn2S4, respectively. The difference in HER enhancement is because different systems lead to different sources of protons, thus affecting hydrogen evolution activity. Theoretically, we further demonstrate that the Ni-Mo-S nanosheets have a narrower band gap than MoS2, which is conducive to the rapid transfer of charge carriers and thus result in multi-photocatalytic reaction systems with excellent activity. The proposed atomic doping strategy provides a simple and promising approach for the design of photocatalysts with high activity and stability in multi-reaction systems.

One-dimensional ultrathin nanowires (NWs) offer a great deal of promising properties for electrochemical energy storage and conversion due to their nanoscale confinement effect and high surface-to-volume ratios. It is highly desirable to precisely design and synthesize ultrathin Ti3C2 NWs in the aspect of size, crystalline structure and composition. Here, we report a simple alkalization strategy to design the ultrathin Ti3C2 NWs for hydrogen evolution reaction (HER) by modulating the surface-active sites. The design principle can well improve the amount of the defect sites and ion accessibility to increase the interactions between Ti3C2 NWs and H*. The optimized Ti3C2 NWs achieve an overpotential of 476 mV at the current density of 10 mA/cm2 and a Tafel slope of 129 mV/dec for HER catalysis, which are superior to that of Ti3C2 nanosheets and m-Ti3C2. It paves an avenue for the rational transformation of MXene bulks to one-dimensional NWs catalysts for HER.