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MoS 2 /a-C:Si composite films doped with different contents of carbon (C) and silicon (Si) were deposited using a hybrid deposition system consisting of a superimposed high-power impulse magnetron sputtering (HiPIMS)-direct current magnetron sputtering (DCMS) and a mid-frequency magnetron sputtering (MFMS). The content of C and Si elements in the films was controlled by changing the direct current (DC) of the graphite-silicon (C-Si) mosaic target. The effects of C and Si doping on the microstructure and mechanical properties of the films were investigated. In addition, the tribological behavior of the films in high-temperature air (up to 350 °C) and vacuum environments was evaluated in detail. The results suggested that MoS 2 /a-C:Si composite films exhibited excellent tribological properties in both high-temperature air and vacuum environments. MoS 2 /a-C:Si composite films doped with C and Si elements exhibited low coefficient of friction (COF) and wear rate (W R) at elevated temperatures due to the improved thermal stability. In particular, MoS 2 /a-C:Si composite film with 40.37 at% C displayed a low COF of 0.051 and a low W R of 1.47 × 10 −6 mm3/(N·m) at 350 °C in air. Moreover, MoS 2 /a-C:Si composite film also exhibited excellent tribological properties under vacuum conditions due to the precipitation of C on the wear track surface. The COF of MoS 2 /a-C:Si composite film with 40.37 at% C under vacuum conditions was as low as 0.018, and the W R of the film was as low as 1.99 × 10 −7 mm3/(N·m). [Display omitted] • MoS 2 /a-C:Si composite films were deposited by a hybrid deposition technique. • The effects of C and Si elements doping on the structure and properties of the films were investigated. • Tribological behavior of the films in high-temperature air (up to 350 ℃) and vacuum environments were evaluated. • MoS 2 /a-C:Si films exhibited excellent tribological properties in both high-temperature air and vacuum environments. • Friction coefficient of the film under vacuum condition was 0.018 and wear rate was 1.99 × 10 −7 mm3/(N·m). [ABSTRACT FROM AUTHOR]

Silicon and its oxides remain the most promising and alternative anode materials for increasing the energy density of Li-ion batteries (LIBs) due to their high theoretical specific capacity and suitable operating voltage. However, the severe volume change effect and rapid capacity attenuation problem make the design and advancement of silicon-based anode materials still challenging for state-of-the-art lithium-ion battery technology. Fortunately, metal-organic frameworks (MOFs) have been widely attracted as emerging materials in energy storage and conversion due to their tunable properties, outstanding morphological and structural advantages. The application of MOF and its derivatives to recast the energy storage properties of silicon and its oxides anode materials is an intriguing approach, where the silicon and its oxide can be embedded into MOF and its derivatives to generate the unique composite anode materials. Besides, the stability of the electrode materials can be significantly improved by adjusting and maintaining the composition and pristine structure of the MOF. However, it is still a great challenge that how to make MOFs better coated on silicon-based materials and what type of MOFs to choose for modification. Concentrating on the above key points, this review paper focuses on the application of MOFs and their derivatives in improving the rational design of silicon and its oxides for Li-ion battery anodes, comparing the advantages and disadvantages of different preparation methods, and discussing the lithium storage mechanism of as-synthesized MOF-modified silicon-based materials, which shows practical significance for the subsequent research in energy storage systems. [ABSTRACT FROM AUTHOR]

Obtaining excellent mechanical properties and high electrical conductivity for ceramic/metal composites is of great significance. In this study, the Ti 3 SiC 2 /Cu composite coatings (20 wt% and 50 wt% Ti 3 SiC 2) were prepared by plasma spraying with the agglomerated Ti 3 SiC 2 /Cu powders. The effects of Ti 3 SiC 2 content on the microstructure, mechanical properties, electrical conductivity and tribological properties of the coatings were analyzed. The results showed that besides the primary compound region, the diffusion and decomposition zones also coexisted within the coatings. The 20 wt% Ti 3 SiC 2 /Cu composite coating showed a denser microstructure with the highest microhardness of 224 HV 0.1 , whereas higher fracture toughness was obtained for the 50 wt% Ti 3 SiC 2 /Cu coating (1.26 MPa•m1/2). Moreover, the 20 wt% and 50 wt% Ti 3 SiC 2 /Cu composite coatings had considerably high electrical conductivity, with the values of 7.9 × 106 S/m and 4.3 × 106 S/m, respectively. Compared to dry friction, the friction coefficient of the coating increased under current-carrying condition, and the wear of the tribo-pairs was accelerated. Generally, the main wear mechanisms of the 50 wt% Ti 3 SiC 2 /Cu composite coating under dry friction and current-carrying conditions are the adhesion wear, abrasive wear and fatigue wear. • Ti 3 SiC 2 /Cu composite coatings were prepared by supersonic plasma spraying. • Effects of Ti 3 SiC 2 content on the coating microstructure and properties were investigated. • Friction and wear properties of the 50 wt% Ti 3 SiC 2 /Cu composite coating under current-carrying condition were analyzed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Spinel LiNi0.5Mn1.5O4 was synthesized by gelatin-assisted method. [•] Moderate amount of gelatin optimize the spinel structure and morphology. [•] LNMO-6 cathode exhibits enhanced cycling stability and rate performance. [•] LNMO-6 cathode displays smaller interface impedance including RSEI and Rct. [ABSTRACT FROM AUTHOR]

Abstract: The lithium-doped carbon clusters LiC n , , and (n =1–10) have been investigated systemically with density functional theory (DFT) method at the B3LYP/6-311+G* level. According to the total energies of different kinds of isomers, the LiC n , , and (n =1–10) clusters have Li-terminated linear ground states structures, except for LiC2, LiC3, , and (n =4–6). The incremental binding energies are evaluated to elucidate the stabilities of the clusters with different numbers of carbon atoms for neutral molecules, cations, and anions, respectively. Clear even–odd alternation effects are observed for the stability of the cationic clusters and anionic clusters, while for neutral LiC n clusters the alternation effect is less pronounced. Similarly, the ionization potentials and electron affinities of LiC n also express an obvious parity alternation. In addition, the most favorable dissociation channels are acquired according to the fragmentation energies accompanying various pathways. [Copyright &y& Elsevier]

A pulse laser with a wavelength of 1064 nm and a pulse width of 1 µs was used to experiment on the coating of a 2024 aluminum alloy surface. The removal performance of the pulse laser cleaning coating was explored by a single factor analysis and orthogonally conditions, and the effects of the laser power, scanning speed, and pulse frequency on the quality of laser coating removal were summarized. The mechanisms of pulse laser cleaning the coating were studied. The results show that the three parameters of the laser power, scanning speed, and pulse frequency have different effects on the quality of laser coating removal. Among them, with the increase of the scanning speed and pulse frequency, the quality of laser cleaning first increases and then decreases, respectively. With the increase in laser power, the quality of laser cleaning increases. A good laser cleaning quality can be achieved at the laser power of 16.5 W, a scanning speed of 600 mm/s, and a pulse frequency of 30 kHz. The laser cleaning coating involves a variety of mechanisms such as combustion, explosion, gasification, thermal vibration stripping, and laser plasma impact. The result can provide practical references for a better searching of the paint removal.

Transition metal oxides (TMOs) have received significant consideration. Because of their enormous theoretical capacity, cheap, and less toxicity. Notably, cobalt-based materials hold promises as negative electrode materials for batteries, but they suffer from less electrical conductivity and significant volume changes during operation. In order to address these challenges, sacrificial templating techniques at the nanoscale offer a potential solution for improving the electrochemical stability and rate performance of these materials. More specifically, these tactics have proven popular for designing Li-ion storages. To ascertain the impact of multiple metal ions on the electrochemical capacity, metal organic frameworks (MOFs) derived MCo 2 O 4 -MOF (M = Zn, Ni, Cu) were developed. Among these, ZnCo 2 O 4 showed the best electrochemical performance (927.2 mAh g -1 at 0.1 A g -1 after 250 cycles). Furthermore, calculations based on density functional theory (DFT) revealed that ZnCo 2 O 4 had the lowest Li + adsorption energy, with a minimum value of -1.61 eV. Moreover, this research aims to design controllable nanostructures in order to enhance the design of transition bimetallic oxide composites for energy storage applications., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Lithium‑sulfur batteries (LSBs) are gradually replacing conventional lithium-ion batteries (LIBs), credited to their high theoretical capacity, low cost, and non-toxicity. Nevertheless, the substantial capacity degradation caused by the polysulfide shuttling during charging and discharging has seriously hindered the commercialization of LSBs. Separator modification with functionalized carbon materials has been found to catalyze the breakdown of polysulfides, thereby improving the efficiency of LSBs. Herein, we synthesized Ni/Co-PBAs with KB structures to subsequently derive Ni/Co/KB composites by a carbonization process, which were later used as a modifier layer on the barrier in LSBs in order to effectively alleviate the shuttle problem. The capacity of the Ni/Co/KB composite decorated separator is found to be 1032 mAh/g at 0.5 C with a coulombic efficiency closer to 100%. In the long-term cycling capability evaluation, the initial cycle is approximately 802.9 mAh/g at 1 C, while capacity retention after 400 cycles is also 678.8 mAh/g, with a high-capacity retention rate of 84.5%. The potential of these composites as modifying materials for superior LSBs separators is verified by experimental and theoretical methods., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Lithium-sulfur (Li-S) batteries have a high specific capacity of 1675 mAh g -1 and are considered to be a promising next-generation energy storage system. A sulfur host for loading Co 4 N nanoparticles into porous carbon has been designed as the cathode for high-performance Li-S batteries. The porous carbon successfully confines sulfur and Co 4 N in the pores, and the synergistic effect of physical and chemical adsorption can effectively inhibit the dissolution and diffusion of polysulfides. Besides, the Co 4 N nanoparticles can also catalyze the redox reaction kinetics. At a current density of 0.5 C, S@KJ-Co 4 N cathodes deliver a high specific discharge capacity of 958.3 mAh g -1 and retain at 784.0 mAh g -1 after 200 cycles, corresponding to a decay rate of 0.09% per cycle. It is believed that this work can provide a promising strategy for the design of many energy storage systems.