Few-Layer MoS2 Nanosheet/Carbon Nanotube Composite Films for Long-Lifetime Lithium Storage and Hydrogen Generation

MoS2 nanomaterials show excellent high theoretical performance in energy storage and hydrogen evolution reaction (HER), whereas they typically suffer from agglomeration and poor electrical conductivity. In this study, unique few-layer molybdenum disulfide nanosheet/carbon nanotube (MoS2/CNT) films are fabricated via an electrochemical exfoliation method. On the one hand, owing to the coupling effects of well-dispersed few-layer MoS2 nanosheets and excellent conductive CNTs, these state-of-the-art films not only afford a short ion-diffusion distance and a fast electron-transport path but also provide abundant active sites and maximized reaction interfaces as well. On the other hand, these free-standing films are capable of being directly used as electrodes without requiring additives, endowing the clean interfaces with reduced charge-transfer resistance. As a result, the few-layer MoS2/CNT films demonstrate a much lower capacity decay rate (0.01%) over 8000 cycles as an anode material of Li-ion batteries and superior hydrogen generation performance with an optimal Gibbs free energy for hydrogen adsorption (ΔG H*) as a catalyst of HER, in contrast to the various MoS2-based nanomaterials.