Fabrication of nanoporous Pd with superior hydrogen sensing properties by dealloying

Abstract Nanoporous Pd ribbons can be fabricated by dealloying a rapidly solidified Al 77 Pd 23 alloy under free corrosion conditions. The nanoporous Pd exhibits a typical bicontinuous interpenetrating cluster–channel structure. The clusters are composed of parallel rods, with large channels between them. The rods are also nanoporous and exhibit an ultrafine ligament/channel structure. Hydrogen sensing properties of the nanoporous Pd ribbons were investigated by measuring the electrical resistance changes of the samples under N 2 –H 2 flow. Nanoporous Pd ribbons were found to have a quick response and a detection limit as low as 0.01 vol%. Considering the simplicity of fabrication as well as the good sensitivity, the present nanoporous Pd is promising in sensing applications.