Nanoporous metal/metal-oxide composite prepared by one-step de-alloying AlNiCoYCu metallic glasses

A bicontinuous nanoporous NiCoCuY metal/metal-oxide composite was fabricated by one-step de-alloying Al85-xNi6Y6Co3Cux (x = 1, 3 and 5) metallic glasses in alkaline solutions. The electro-chemical performance of the nanoporous composites as binder-free electrodes has been evaluated. It is found that 3 at.% Cu addition can achieve the largest capacitance which is attributed to the increase in electric conductance. The capacitance of nanoporous composites can reach as high as 1.22 F cm−2 if the Al82Ni6Y6Co3Cu3 sample was de-alloyed in 4 M KOH for 50 min. Such a one-step strategy of de-alloying metallic glass not only generates a promising functional material for energy storage, but also provides a facile way for decreasing the resistance of electrode material.