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Hollow metallic nickel spheres with an average diameter of 1.8 µm have been successfully synthesized via a decomposition and reduction route by using hollow nickel hydroxide spheres as precursor. Microsized hollow bimetallic (Ni/Au, Ni/Ag, Ni/Pt, and Ni/Pd) and noble metal (Pt and Pd) spheres have also been selectively synthesized by adjusting the amount of reactants of replacement reaction in which corresponding noble metal compound and hollow metallic nickel spheres were used as starting materials. The magnetic properties of hollow metallic nickel spheres have been investigated. It is found that the coercivity of hollow Ni spheres is much enhanced compared with their bulk counterparts. The study on catalytic activities of the as-prepared hollow noble metal spheres for hydrogen generation reveals that Ni/Pt hollow bimetallic spheres exhibit favorable catalytic activities which have potential applications in portable hydrogen generation systems.

Several potential new phosphorus-containing flame retardant molecules were evaluated for heat release reduction potential by incorporation of the molecules into a polyurethane, generated from methylene diphenyl diisocyanate and 1,3-propane diol. The heat release reduction potential of these substances was evaluated using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods to qualitatively evaluate their potential reactivity into the polyurethane prior to heat release testing. The functionality of the flame retardants was epoxide based that would potentially react with the diol during polyurethane synthesis. Flammability testing via PCFC showed that the heat release reduction potential of each of the flame retardants was structure dependent, with phosphates tending to show more effectiveness than phosphonates in this study, and alkyl functionalized phosphorus groups (phosphate or phosphonate) being more effective at heat release reduction than cyclic functionalized groups.

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Red phosphorus (RP) is considered to be the most promising anode material for lithium-Ion batteries (LIBs) due to its high theoretical specific capacity and suitable voltage platform. However, its poor electrical conductivity (10−12 S/m) and the large volume changes that accompany the cycling process severely limit its practical application. Herein, we have prepared fibrous red phosphorus (FP) that possesses better electrical conductivity (10−4 S/m) and a special structure by chemical vapor transport (CVT) to improve electrochemical performance as an anode material for LIBs. Compounding it with graphite (C) by a simple ball milling method, the composite material (FP-C) shows a high reversible specific capacity of 1621 mAh/g, excellent high-rate performance and long cycle life with a capacity of 742.4 mAh/g after 700 cycles at a high current density of 2 A/g, and coulombic efficiencies reaching almost 100% for each cycle.