Nanoporous Copper Fabricated by Dealloying Single-Phase Mn-Cu-Al Alloy and Its Non-Enzymatic Glucose Detection

Single-phase ternary Mn-Cu-Al alloy ribbons were fabricated by melt-spinning a Mn48Cu28Al24ingot on a rotating copper roller. They were used as dealloying precursor for forming the nanoporous structure in HCl solution. The basic dealloying behavior was examined by controlling the dealloying time from 5 min to 180 min at 50 °C. Due to the active chemical property, Mn and Al elements are easily etched in acid solutions. Meanwhile, Cu elements retained and rearranged. A three-dimensional bicontinous nanoporous structure was fabricated, with a ligament size of 55 nm~100 nm and pore size of 35 nm~85 nm. The porosity evolution of dealloyed MnCuAl alloy was divided into three stages. First, the dissolution of Mn and Al is so significant that formation of pores is dominant. Stage two, the rapid growth of both ligament size and pore size. The ligament/pore ratio is nearly unchanged. The last stage is ligament coarsening. Moreover, the electrocatalytic activity for glucose oxidation of dealloyed samples is examined. The 40 min dealloyed MnCuAl ribbon exhibited the highest sensitivity and relatively maximum current density.