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High thermal conductivity materials are an urgent need for high power, microelectronic components and equipment, but are limited by low thermal conductivity of the traditional silicone materials. 4-Cyano-4'-n-octyl biphenyl (8OCB) was synthesized to modify carbon nanotubes, and silicone was used as the matrix. In the curing process of the composite, an electric field was applied and the liquid crystal induced the orientation of carbon nanotubes in the direction of 8OCB liquid crystal. The morphology, structure and properties of modified carbon nanotubes and composites were characterized by Fourier transform infrared spectroscopy, polarized microscopy, transmission electron microscopy, thermal conductivity, and so on. The 8OCB liquid crystal can improve the dispersion of carbon nanotubes in silicone composites. When the mass fraction of multiwalled carbon nanotubes (MWCNTs) was llwt%, the thermal conductivity of 8OCB-MWCNTs/silicone composite after electric field was 2.39 W/(m K), which is 6.4 times that of MWCNTs/silicone composite after electric field and 15.5 times that of pure silicone matrix. A method to obtain highly ordered filled thermal conductive materials by applying an electric field to induce the orientation of carbon nanotubes is demonstrated. KEYWORDS carbon nanotubes, liquid crystal, organic silicon, thermal conductivity, 1 | INTRODUCTION Silicone resin has the advantages of high- and low-temperature resistance, radiation resistance, oxidation resistance, weather resistance, and so forth. This resin is widely used in electronic appliances, [...]

Three-dimensional (3D) carbon matrix composites have been widely used in the field of lithium-ion batteries due to their unique structure and properties. In this work, we employ a rapid method to synthesize a ternary composite (MoS2/carbon-FeOx) with a 3D hierarchical nanostructure via hydrothermal and microwave irradiation treatment. The 3D hierarchical nanostructure is composed of 0D nanoparticles (ultra-small iron oxide), 1D carbon nanotubes, and 2D nanosheets (MoS2 nanoflowers and graphene), providing extraordinary mechanical and electrochemical stability during the lithiation/delithiation process. As expected, when employed as an anode material, the 3D hierarchical nanostructure delivered a high reversible capacity of 740 mAh g–1 without any fading tendency after 100 cycles at a current density of 0.2 A·g–1, and retained over 508 mAh g–1 even surveyed by a high current density of 2 A g–1. [ABSTRACT FROM AUTHOR]

Photocatalytic (PC) overall water splitting (OWS) is considered an ideal method for solar-to-fuel conversion, though its practical application is greatly limited by the loading of noble-metal co-catalysts. It is, therefore, of great significance to explore alternate non-noble-metal co-catalysts. Herein, a novel non-precious metal Mn2Co2C@C/Mn2N0.86 composite (denoted as MCMN), composed of Mn2N0.86 and N-doped graphitized carbon wrapped Mn2Co2C nanoparticles, was fabricated and then used to modify photocatalysts, such as g-C3N4 and SrTiO3 for the construction of MCMN/g-C3N4 and MCMN/SrTiO3 composite photocatalysts by a mechanical grinding method. When they were used for PC OWS under UV-Vis light irradiation, in the initial stage, the Mn2N0.86 in MCMN was hydrolyzed, and novel non-precious metal MnOOH and Mn2Co2C@C (MC) dual cocatalysts were photo-derived to grow in situ on the surfaces of photocatalysts. In the new kind of MC/g-C3N4/MnOOH PC system, the metallic MC acts as a co-catalyst for H2 generation, effectively trapping photoelectrons and accelerating H2 evolution reaction; meanwhile, MnOOH acts as a co-catalyst for O2 generation, favoring the adsorption of water molecules on the surface to boost the O2 evolution reaction. Consequently, the optimized MC/g-C3N4/MnOOH showed a prominent H2 evolution rate of 8.876 μmol h−1 for PC OWS, even higher than that of g-C3N4 loaded with 1 wt% Pt, and the corresponding AQE reached 2.54% and 1.45% at 400 and 420 nm, respectively. A similar promotion was also obtained on the SrTiO3 photocatalyst, demonstrating the versatility of this composite. This work provides a new avenue for the construction of novel noble-metal-free PC systems. [ABSTRACT FROM AUTHOR]

Novel SnO2/SiC hollow sphere nanochains were synthesized by topological morphology conversion of SnO2@C core–shell nanochains through a vapour–solid reaction. Evaluation of the SnO2/SiC HSNCs for the generation of hydrogen revealed that they exhibit excellent catalytic activity and durability. [ABSTRACT FROM AUTHOR]

Formic acid is an appealing hydrogen storage material. In order to rapidly produce hydrogen from formic acid under relatively mild conditions, high-efficiency and stable photocatalytic systems are of great significance to prompt hydrogen (H2) evolution from formic acid. In this paper, an efficient and stable photocatalytic system (CdS/P/MoS2) for H2 production from formic acid is successfully constructed by elemental P doping of CdS nanorods combining with in situ photodeposition of MoS2. In this system, P doping reduces the band gap of CdS for enhanced light absorption, as well as promoting the separation of photogenerated charge carriers. More importantly, MoS2 nanoparticles decorated on P-doped CdS nanorods can play as noble-metal-free cocatalysts, which increase the light adsorption, facilitate the charge transfer and effectively accelerate the hydrogen evolution reaction. Consequently, the apparent quantum efficiency (AQE) of the designed CdS/P/MoS2 is up to 6.39% at 420 nm, while the H2 evolution rate is boosted to 68.89 mmol·g−1·h−1, which is 10 times higher than that of pristine CdS. This study could provide an alternative strategy for the development of competitive CdS-based photocatalysts as well as noble-metal-free photocatalytic systems toward efficient hydrogen production. [ABSTRACT FROM AUTHOR]

Photocatalytic elimination of antibiotic pollutant is an appealing avenue in response to the water contamination, but it still suffers from sluggish charge detachment, limited redox capacity as well as poor visible light utilization. Herein, a particular S-scheme FeOOH/MgIn 2 S 4 heterojunction with wide visible light absorption was triumphantly constructed by in-situ growth of MgIn 2 S 4 nanoparticles onto the surface of FeOOH nanorods, and employed as a high-efficiency visible light driven photocatalyst for removing tetracycline (TC). Conspicuously, the as-obtained FeOOH(15 wt%)/MgIn 2 S 4 elucidated the optimal TC removal rate of 0.01258 min -1 after 100 min of visible light illumination, which was almost 33.1 and 6.6 times larger than those of neat FeOOH and MgIn 2 S 4 , separately. The exceptional degradation performance was principally put down to the establishment of S-scheme heterojunction between FeOOH and MgIn 2 S 4 , which could not merely accelerate the detachment of photogenerated carriers, but also retain the powerful reducing ability of photoinduced electrons for MgIn 2 S 4 and high oxidizing capacity of photoexcited holes for FeOOH, strongly driving the generation of plentiful active species including holes, superoxide and hydroxyl radicals. Additionally, the possible degradation mechanism and pathways of TC were also speculated. This work offers a valuable perspective for constructing high-efficiency S-scheme heterojunction photocatalysts for eradicating antibiotics., (Copyright © 2022 Elsevier Ltd. All rights reserved.)