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CuCo 2 S 4 with core-shell structure was prepared by ion exchange self-template method, and the microwave absorption property of CuCo 2 S 4 with this morphology was studied. At 30% filling, the maximum effective bandwidth is 4.88 GHz (13.12–18 GHz, 2 mm), and the strongest absorption peak is − 25.52 dB (18 GHz, 1.7 mm). In order to optimize the absorption performance of core-shell CuCo 2 S 4 , conductive carbon black nanoparticles were blended with core-shell CuCo 2 S 4 to obtain CuCo 2 S 4 /C composite. Compared with single-phase CuCo 2 S 4 absorber, the maximum effective bandwidth of the composite increased to 6.00 GHz (12.00–18 GHz, 2 mm), and the strongest absorption peak increased to − 52.60 dB (15.42 GHz, 1.9 mm). These results demonstrated that the introduction of small amount of conductive carbon black nanoparticles not only optimize the impedance matching, but also enhance the polarization loss of the composite, therefore, comprehensively improve the microwave absorption performance of the samples. • Core-shell CuCo 2 S 4 is obtained based on an ion-exchange mechanism. • CuCo 2 S 4 /C composites is prepared by directly grinding carbon black with CuCo 2 S 4. • The effective absorption band of composites is much expanded. [ABSTRACT FROM AUTHOR]

Abstract: Carbon coated graphite with high resin and water wettability characteristics could expand the refractory and carbon–carbon composites application in different fields. Improvement of water and resin wettability of graphite using carbon black coating via ink media is reported. Present method is based on preparing colloidal disperion of carbon black in ink followed by adding proper amount of graphite to the mixture which was dried and heat treated at 250°C afterwards. The results showed that by controlling the amount of carbon black in ink and optimizing the process, a uniform coating with a thickness of 50nm could be developed on the graphite surface. The wettability was evaluated by measuring contact angle and the microstructure of samples was characterized by optic microscope (OM) and scanning electron microscope (SEM). Also Raman spectroscopy was employed to support the results. The microstructure of coating was found to be uniform composed of carbon black nanoparticles. It was also demonstrated that the coating that could enhance the phenolic resin wettability was well. We also showed the coating could be applied on other ceramic particles such as MgO. [Copyright &y& Elsevier]

The large-scale applications of lithium-sulfur (Li–S) batteries have been limited by their rapid capacity loss, which can be attributed to the dissolution of polysulfide intermediates and subsequent irreversible shuttling effect. Several strategies have been attempted to solve these problems by designing novel cell structure, including the modification of separator. Herein, we have developed a new carbon black/LiMn 2 O 4 -modified separator for boosting the electrochemical performance of the Li–S batteries. The carbon black (Super P, for short SP) conductive layer plays the roles as an extra current collector for improving the utilization of active materials and a physical obstruction for restraining the diffusion of polysulfide intermediates. The LiMn 2 O 4 (LMO) nanoparticles can chemically adsorb polysulfide intermediates and act as a fast channel for Li ions transportation. The as-prepared Li–S batteries with SP/LMO separators have delivered the discharge capacity of 1378.3 mAh g−1 for the initial cycle at 0.05C and 618.7 mAh g−1 after 300 cycles at 0.5C. The Li–S batteries also possess excellent rate performance and stability, retaining a discharge capacity of 427.1 mAh g−1 even under a high current density of 2 C. The Carbon black/LiMn 2 O 4 -modified separator was prepared by a facile blade-coating method. The carbon black (Super P) conductive layer plays the roles as an extra current collector for improving the utilization of active materials and a physical obstruction for restraining the diffusion of polysulfide intermediates. The LiMn 2 O 4 nanoparticles not only have chemical binding with polysulfide intermediates, but also act as a fast channel for Li ions transportation. Image 1 • Carbon black/LiMn 2 O 4 -modified separator has been synthesized for Li–S battery. • LiMn 2 O 4 has a strong adsorption capability for polysulfides and also promotes the fast transmission of Li ions. • The battery with high sulfur loading using the modified separator exhibited excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Ni/C was successfully synthesized via hydrazine hydrate reduction at room temperature (RT). Pt/C, Ru/C and PtRu/C were prepared via an impregnation method. PtNi/C, RuNi/C and PtRuNi/C were synthesized via a chemical replacement method. The characterization results revealed that PtRuNi nanoparticles (NPs) were highly and uniformly dispersed on carbon black in PtRuNi/C. PtRuNi/C showed a novel nanostructure in which PtRu islands (PtRu nanoclusters or PtRu binary atoms) covered Ni/Ni(OH) 2 NPs. PtRuNi/C trimetallic nanomaterial exhibited an optimum catalytic performance (turnover frequency (TOF) = 211.4 h−1 and selectivity for the production of 1,2,3,4-tetrahydroquinoline (py-THQ) > 99%) in the selective hydrogenation of quinoline at 60 °C under 5.0 MPa H 2. The catalytic properties of PtRuNi/C were significantly improved as compared to bimetallic (PtNi/C, RuNi/C and PtRu/C) and monometallic (Ni/C, Pt/C and Ru/C) nanomaterials due to its unique nanostructure, with an observed nano-synergy effect among Pt-, Ru- and Ni-related species. • PtRuNi/C was with the novel nanostructure of PtRu island-on-Ni/Ni(OH) 2 NPs. • PtRuNi/C has the synergistic effect among Pt, Ru and Ni related species. • PtRuNi/C has excellent catalytic activity for quinoline hydrogenation due to synergistic effect. [ABSTRACT FROM AUTHOR]

Iron/nitrogen co-doped carbon materials (Fe/N-C) have been extensively investigated as oxygen reduction reaction (ORR) catalysts in alkaline medium. Here, Fe 3 O 4 nanoparticles decorated carbon black is encapsulated with polypyrrole and subsequently utilized as a precursor to synthesize a highly efficient ORR catalyst through pyrolysis. Interestingly, this catalyst consists of yolk-shell Fe@FeN x and N-doped porous carbon, demonstrating a synergistically improved ORR activity. It shows better durability, Pt-comparable activity, and superior tolerance against methanol crossover under alkaline conditions. Control experiments confirm that yolk-shell Fe@FeN x nanoparticles provide efficient catalytic sites and facilitate charge transfer in ORRs. Thus, this study provides a new kind of Fe/N-C electrocatalyst synthesized to be nitride rather than carbide simply with a heat-treatment under N 2 atmosphere. Image 1 • Fe@FeN x /N-C consist of yolk-shell Fe@FeN x nanoparticles and N-doped mesoporous carbon. • Fe@FeN x /N-C are synthesized with pyrolysis of polypyrrole-encapsulated Fe 3 O 4 /C. • Yolk-shell Fe@FeN x provides catalytic sites and facilitates charge transfer in ORR. • Fe@FeN x /N-C show excellent ORR activity and durability in alkaline media. [ABSTRACT FROM AUTHOR]