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

Abstract

MoS 2 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 (MoS 2 /CNT) films are fabricated via an electrochemical exfoliation method. On the one hand, owing to the coupling effects of well-dispersed few-layer MoS 2 nanosheets and excellent conductive CNTs, these stateof-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 MoS 2 /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 MoS 2 -based nanomaterials.

Bi nanoparticles confined in N,S co-doped carbon nanoribbons with excellent rate performance for sodium-ion batteries

“…They can also prevent Bi aggregation and buffer the large volume expansion during cycles. 24 The high-resolution TEM (HRTEM) image of the N,S-C@Bi/CNT (Fig. 1d) presents distinct lattice fringes, and the observed lattice distance of 0.32 nm corresponds to the (012) plane of hexagonal Bi crystals (JCPDS No.…”

Flexible and Freestanding MoS2 Nanosheet/Carbon Nanotube/Cellulose Nanofibril Hybrid Aerogel Film for High-Performance All-Solid-State Supercapacitors

“… 15 − 19 The addition of CNT can inhibit the agglomeration and accumulation of MoS 2 nanosheets, expand the layer spacing of MoS 2 , enhance the interlayer conductivity of MoS 2 , and make the redox reaction of MO 4+ go deeper into the interlayer of MoS 2 . 20 − 24 Although CNT can accelerate the electron transfer efficiency of MoS 2 –CNT composite electrodes, the weak interaction between them will significantly reduce the flexibility of composite electrodes and limit its development in flexible supercapacitor. Therefore, we can introduce a certain amount of nanocellulose into MoS 2 –CNT composite electrodes to improve their flexibility.…”

“…It is one of the most convenient and effective ways to improve the electrochemical performance of composite electrodes by compounding with electrode materials that have complementary and synergistic effects on microstructure, crystal structure, electrical conductivity, and electrochemical performance. Among them, carbon nanotube (CNT) with ideal one-dimensional structure, excellent electrical conductivity, and large specific surface area is one of the more ideal carbon materials for the construction of MoS 2 composites. − The addition of CNT can inhibit the agglomeration and accumulation of MoS 2 nanosheets, expand the layer spacing of MoS 2 , enhance the interlayer conductivity of MoS 2 , and make the redox reaction of MO 4+ go deeper into the interlayer of MoS 2 . − Although CNT can accelerate the electron transfer efficiency of MoS 2 –CNT composite electrodes, the weak interaction between them will significantly reduce the flexibility of composite electrodes and limit its development in flexible supercapacitor. Therefore, we can introduce a certain amount of nanocellulose into MoS 2 –CNT composite electrodes to improve their flexibility.…”

Acetylation Strategy for Unzipping Carbon Nanotubes in High-Performance Lithium-Ion Batteries

“…Carbon nanotubes (CNTs) have been intensively explored since 1991 because of their extraordinary features, including the high electrical conductivity, stability, and superior mechanical characteristics, as well as the alkali metal redox ability. − Many researchers have validated the practical use of this material as catalysts, composites, and molecular wires, besides theoretical considerations on the potential as an inherently one-dimensional conducting polymer. − However, many researchers have discovered that the structure, shape, and production technique of CNTs imposed a significant impact on their electrochemical performance when employed as LIB materials. ,, For example, CNTs prepared by chemical vapor deposition displayed good specific capacity at low current density, but they suffered from high irreversible capacity and severe voltage hysteresis. , Furthermore, various studies have shown that etching, ball milling, and oxidation treatment could improve the reversible capacity of CNTs. For example, Gao et al .…”