In English

PdAu Alloy Nanoparticles for Hydrogen Sensing

emil lindström
Göteborg : Chalmers tekniska högskola, 2014. 49 s.
[Examensarbete på avancerad nivå]

The potential of a hydrogen economy introduces the need for ecient hydrogen storage as well as reliable gas sensors. Hydride-forming metal particles may be the solution to both these problems. In this thesis we present a means of fabrication of PdAu alloy nanoparticles, suitable for LSPR sensing of hydrogen gas concentrations. Heterogeneous particles of stacked Pd+Au layers were fabricated using Hole-Mask Colloidal Lithography. The particles were annealed at di erent temperatures in order to promote alloying. Full alloying seems to be achieved at 500 C, as was con rmed by XPS measurements and by hydrogen uptake characteristics. Hydrogen ab-/desorption cycles were measured by monitoring the LSPR spectra of the particles while varying the hydrogen pressure. The hysteresis of the a-b transition decreased with increasing gold content, in agreement with measurements on thin lms. The hydrogen ab-/desorption kinetics were faster for PdAu than for pure Pd particles and the rate limiting steps seem to be di erent. Addition of Au may improve optical hydrogen sensors based on Pd. Nanoparticles may prove bene cial over thin lms due to the possibility of LSPR sensing and faster kinetics due to shorter di usion.

Publikationen registrerades 2014-02-26.

CPL ID: 194180

Detta är en tjänst från Chalmers bibliotek