Lithium (Li) dendrites formed from nonuniform Li deposition limit potential uses of Li metal as an anode material. Here, we report a lithiophilic 3D porous CuZn current collector that mitigates dendrite formation and realizes the high stability of Li anodes. As opposed to the common metal current collector of copper (Cu), calculations and in situ experiments demonstrate that copper zinc (CuZn) alloys found in commercially available brass are lithiophilic and promote uniform Li deposition. Facile dealloying methods are applied to provide sufficient Li deposition and volume expansion space in brass sheets. Residual CuZn alloys in the framework are found to induce uniform Li deposition and stabilize Li dendrite growth. The optimal current collector (2h-3D CuZn) runs smoothly over 220 cycles at 0.5 mA cm −2 with improved Coulombic efficiencies at high current density. This demonstrates an economic and facile CuZn preparation method that unlocks the full potential of Li anodes and provides new Li battery stabilization approaches.

A composite poly(D,L)lactic acid (PDLLA)/hydroxyapatite (HA) biomaterial was prepared by in situ polymerization of D,L-lactide monomer and HA. Supercritical CO2 (SC CO2) technology was developed to prepare the biodegradable composite foams for use in tissue regeneration. In this technology, NaCl particles were used as porogen to produce an open-pore structure. Organic solvents were not used and high temperature was not necessary. The problem with pore interconnectivity was resolved. High-porosity composite foams (up to 90% +/- 2% porosity) were obtained with pore sizes ranging from 100 to 300 microm suitable for cell seeding. The microstructure and morphology of the composite foams could be controlled by saturation pressure, saturation time, and temperature as well as amount of NaCl particles. The compressive strength and water absorbability of the composite foams were also determined. With an increase in HA amount, the molecular weight of PDLLA/HA composite foams decreased, but the mechanical strength and hydrophilicity increased slightly.

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