1 research outputs found
Effect of Rhodium Distribution on Thermal Stability of Nanoporous Palladium–Rhodium Powders
Powders of nanoporous palladium and palladium alloy particles
are
of potential value for storage of hydrogen isotopes, as long as the
pores remain stable over a useful range of temperatures and chemical
environments. Rhodium alloys are known to have enhanced hydrogen storage
and improved thermal stability versus pure palladium. However, the
distribution of rhodium on pore and particle surfaces is critical
to this. Pores are more ordered and thermally stable in rhodium-rich
regions. Treatment of particles at elevated temperature under reducing
conditions can cause rearrangement of Rh and Pd at the surface, but
not a major change in Rh distribution throughout the particle. Heating
in the presence of hydrogen causes more rapid pore rearrangement than
heating in vacuum subsequent to hydrogen exposure, suggesting a direct
chemical influence of hydrogen on mobility of surface atoms. These
results provide a clear path to future improvements in the stability
of nanoporous metals in reducing atmospheres