Polyhedral Au-Pd core-shell nanocrystals as highly spectrally responsive and reusable hydrogen sensors in aqueous solution

Abstract

Absorption signals absorption: The surface plasmon resonance absorption band of tetrahexahedral, octahedral, and cubic Au-Pd core-shell nanocrystals with gold nanocrystal cores was strongly red shifted upon hydrogen absorption into the Pd shell. This reversible spectral shift makes the nanocrystals promising recyclable hydrogen-gas sensors. Hydrogen absorption could even be detected visually with smaller core-shell octahedra (see picture). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.