Microstructure Evolution of Nanoporous Copper Fabricated by Electrochemical Dealloying Mn-Cu Alloy

The electrochemical dealloying behavior of single-phase Mn-Cu alloy in hydrochloric acid solution by applying different dealloyed voltages was investigated. The concentrations of HCl solution are also explored as a parameter for modulating the nanoporous microstructure. Phase constitution and microscopic morphology of precursor alloy and dealloyed samples were characterized using X-ray diffraction and scanning electron microscopy. The precursor alloy was single-phase CuMn4 solid solution. After dealloying, only face-centered cubic copper phase can be identified. The results show that different applied voltages make a small difference on nanoporous structure. The concentration of hydrochloric acid solution has a remarkable influence on the dealloying process and nanoporous microstructure. The dealloying in a 0.5 M HCl solution results in nanoporous copper with ligament size range of 43.76-160.66 nm. The high concentration of dealloying solution leads to the formation of coarsened nano structure.