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A functionalized carbon nanotube (FCNT)/Ni(HCO3)2-Ni nanostructures were synthesized by decorating nanoflaky and mesoporous Ni(HCO3)2 onto FCNT along with in situ formed reduced metallic Ni for the...

A well-structured anode nanomaterial, which can ensure electron and ion transport and avoid excessive pulverization, is of crucial importance to achieve high capacity with superior cycling stability for both sodium- and lithium-ion batteries (SIBs and LIBs). For the purpose of a superior rate performance, this work here has designed and successfully synthesized a new Na+/Li+ storage nanomaterial of SCS/Sn2Fe@GO through loading of a Sn2Fe nanoalloy on sea-sponge-like carbon spheres (SCSs), followed by a graphene oxide (GO) wrapping process. In such a designed composite, the SCS skeleton ensures electronic conductivity and shorts Na+ and Li+ diffusion pathways, while the Sn2Fe nanoalloy delivers a high capacity and prevents excessive pulverization. The GO shell around SCS/Sn2Fe greatly enhances the cyclability. Used as an anode, the SCS/Sn2Fe@GO nanocomposite enables a high capacity up to 660 mAh g–1 at 50 mA g–1, which is maintained without decay up to 800 cycles in SIBs, and up to 850 mAh g–1 at 500 mA g–...

To meet the demands of long cycle life under high rate for lithium-ion batteries, the advancement of anode materials with stable structural properties is necessarily demanded. Such promotion needs to design reasonable structure to facilitate the transportation of electron and lithium ions (Li+). Herein, a novel C/Fe3O4 sea-sponge-like structure was synthesized by ultrasonic spray pyrolysis following thermal decomposition process. On the basis of sea-sponge carbon (SSC) excellences in electronic conductivity and short Li+ diffusion pathway, nano-Fe3O4 anchored on stable SSC skeleton can deliver high electrochemical performance with long cycle life under high rate. During electrochemical cycling, well-dispersed nano-Fe3O4 in ∼6 nm not only averts excessive pulverization and is enveloped by solid electrolyte interphase film, but also increases Li+ diffusion efficiency. The much improved electrochemical properties showed a capacity of around 460 mAh g–1 at a high rate of 1.5C with a retention rate of 93%, whi...

Development of highly stabile battery-type electrode materials with superior capacity has been a critical challenge for hybrid supercapacitors. We report a high-performance electrode material, tubular sandwich-structured CNT@Ni@Ni2(CO3)(OH)2, synthesized via a scalable, dynamic, controlled in situ reduction–chemical deposition process. Applied as a battery-type electrode material, this novel nanostructure exhibits excellent electrochemical stability, majorly attributed to the Ni midshell serving a dual role as “capacity supplement” and “electron highway”, which, to our knowledge, was incorporated into the nanocomposite electrodes for the first time. Also benefiting from the high conductivity of carbon nanotubes (CNTs) and the high capacity of the amorphous NiOOH ultrathin film [converted from the Ni2(CO3)(OH)2 outer shell], the resulting CNT@Ni@Ni2(CO3)(OH)2 material as a battery-type electrode achieves a superior capacity of 221 mAh·g–1 at 5 A·g–1 with 76% capacity retention at 50 A·g–1 and maintains 81%...

Ni(OH) 2 /CNTs/Ni(OH) 2 lamellar-crossing-nanostructure with a single lamellar spacing of ∼5 nm was effectively constructed through two-phase-interface reaction process followed by the CNTs crossed among the lamellar-nanostructured Ni(OH) 2 . The resultant nanocomposite can offer large active surface areas and short diffusion paths for electrons and ions, and is investigated as a potential pseudocapacitor electrode material for electrochemical energy storage applications. Electrochemical data demonstrate that the as-prepared nanocomposite exhibits a high specific capacitance of ∼1600 F g −1 at the scan rate of 1 mV s −1 in 6 M KOH solution at normal pressure and temperature, which is great higher than Ni(OH) 2 (∼1200 F g −1 ). Furthermore, Ni(OH) 2 /CNTs/Ni(OH) 2 nanocomposite shows a higher energy density (∼125 Wh kg −1 , 2 A g −1 ) and has a slightly decrease of 5% in specific capacitance after 1000 continuous charge/discharge cycles.

Magnetic Ru-capped/FeCo nanoflowers are solvothermally synthesised through a self-catalytic growth and assembly process. The synthesised Ru-capped/FeCo nanoflowers (∼3.63 μm) consist of Ru-capped FeCo nanorods with an average diameter of ∼13 nm and a length ranging from 1.33 to 2.1 μm. A vibration sample magnetometer measurement reveals that the ferromagnetic behaviours depend on nanomaterial composition. Particularly, an appropriate quantity of Fe in the composition improved catalytic activity. The Fe 22 Co 73 /Ru 5 nanoflowers exhibits the highest catalytic activity towards NaBH 4 hydrolytic dehydrogenation at ambient pressure and room temperature (the dehydrogenation rate is 4293.75 mL min −1 g −1 ; the activation energy is 42.95 kJ mol −1 ).

A new magnetic Pt-loaded NiCo nanochain, with the diameter from 80 nm to 120 nm, has been prepared through microwave-induced assembly process followed by the galvanic displacement performance. Pt nanoparticles are distributed on the surface of NiCo nanochains. The products are investigated as hydrolytic dehydrogenation catalyst for potential hydrogen energy applications. Compared with NiCo nanochains, the Pt-loaded NiCo nanochains present exceedingly high catalytic activity toward the hydrolytic dehydrogenation of ammonia borane aqueous under ambient atmosphere at room temperature, where the Ni16Co80/Pt4 nanochains exhibit high catalytic activity with a lower activation energy of 45.72 kJ mol(-1) and a superior dehydrogenation rate of 1.17 × 10(4) mL min(-1) g(-1), suggesting the potential application in hydrogen fuel and chemical industry.

Uniform NiCo alloy hexagonal nanoplates were synthesized through a formaldehyde molecule controlled growth process. They are investigated as a crystal plane selective dehydrogenation catalyst for potential hydrogen energy applications and visible-light synergistic catalysts for nano-ZnO. The resultant NiCo alloy hexagonal nanoplates exert highly efficient crystal plane selective catalytic activity and long-term stability for the hydrolytic dehydrogenation of aqueous ammonia borane under ambient atmosphere at room temperature. Additionally, they exhibit crystal plane selective visible-light-driven enhanced catalysis enhancement for nano-ZnO towards the degradation of methylene blue solution. These results suggest the importance of the rational design and synthesis of NiCo alloy hexagonal nanoplates for high performance hydrogen energy and visible-light-driven catalysis applications.