Flexible supercapacitor electrodes fabricated by dealloying nanocrystallized Al-Ni-Co-Y-Cu metallic glasses

Abstract

Nanoporous oxides of transition metals are of great potential for applications as super-capacitor electrodes because of their variable valence. However, the low conductance of electrons in oxides and slow transportation of ions in nanopores limit their performance. In this work, NiCo-contained metal/metal-oxide nanoporous composites are fabricated by one-step dealloying nanocrystallized Al82Ni6Co3Y6Cu3 (at.%) metallic glass ribbons in KOH solutions. The capacitance of the dealloyed nanoporous composites reaches 3.35 F cm−2 (about 1522 F cm−3), which is 3–10 times higher than that dealloyed from as-spun metallic glass and crystalline precursors. The large capacitance is attributed to the combination of efficient charge transportation rate and high loading amount of active materials. These results demonstrate for the first time that the nanocrystallized metallic glasses are promising easy-processing precursors for fabricating flexible free-standing nanoporous electrodes.