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A single-step fabrication of ZnSb nanostructures using template-free electrochemical deposition was developed. Results have indicated that ZnSb nanoflakes, nanowires, or nanoparticles with controlled composition could be obtained by adjusting the precursor concentration, applied voltage, and substrate type. The ZnSb nanostructures deposited on Cu foils were directly used as Li-ion battery anodes without the addition of any binder. Electrochemical analyses revealed that the interconnected ZnSb nanoflakes depicted high discharge capacities and a stable performance, which were better than that of ZnSb nanowires and nanoparticles. With an initial discharge capacity of 735 mA h/g and an initial Columbic efficiency of 85%, the ZnSb nanoflakes maintained a discharge capacity of 500 mA h/g with a Coulombic efficiency of 98% after 70 cycles at a current density of 100 mA/g (0.18 C). The ZnSb nanowires and nanoparticles showed a capacity of 190 and 40 mA h/g, respectively, after 70 cycles at the same current density. The improved performance of the interconnected ZnSb nanoflakes is attributed to their open structure, with a large surface area and small crystal grains, to facilitate the diffusion of Li ions and to buffer the large volume swings during the lithium intercalation process.

The elastic modulus of metallic orthopaedic implants is typically 6-12 times greater than cortical bone, causing stress shielding: over time, bone atrophies through decreased mechanical strain, which can lead to fracture at the implantation site. Introducing pores into an implant will lower the modulus significantly. Three dimensional printing (3DP) is capable of producing parts with dual porosity features: micropores by process (residual pores from binder burnout) and macropores by design via a computer aided design model. Titanium was chosen due to its excellent biocompatibility, superior corrosion resistance, durability, osteointegration capability, relatively low elastic modulus, and high strength to weight ratio. The mechanical and physical properties of 3DP titanium were studied and compared to the properties of bone. The mechanical and physical properties were tailored by varying the binder (polyvinyl alcohol) content and the sintering temperature of the titanium samples. The fabricated titanium samples had a porosity of 32.2-53.4% and a compressive modulus of 0.86-2.48 GPa, within the range of cancellous bone modulus. Other physical and mechanical properties were investigated including fracture strength, density, fracture toughness, hardness and surface roughness. The correlation between the porous 3DP titanium-bulk modulus ratio and porosity was also quantified.

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