Hydrogen Utilization: Fuel Cells - Hydrogen Generation, Storage, and Utilization - page 158

Discrete low-aspect-
ratio nanoparticles
dispersed on low-aspect-
ratio supports

Discrete low-aspect-
ratio nanoparticles
dispersed on
high-aspect-
ratio supports
Nanoparticles on
multi-walled and
single-walled carbon
nanotubes
Nanoparticles on
standard carbon
fibres

Extended surface area catalysts Unsupported

nanoparticles

Bulk surfaces

High-aspect-ratio
particles

Modulated
surface
structures

Nanoparticles on carbon black
supports, standard and
graphitized

Pt nanowhiskers
Pt, pt-alloy
nanotubes
Pt, monolayers on
metal wires, rods

Single-crystal surfaces De-alloyed

skeletal surface
structures

Shape/size-
controlled
nanoparticles
Standard
nanoparticles

Pt-skin structures

Pt and Pt-alloy
nanoparticles

De-alloyed skin

Low-aspect-ratio
particles
Pt blacks

Polycrystalline

De-alloyed skeletal

Pt monolayer on
PGM cores

Manufactured
screens, meshes

Pt-alloy blacks
Pt-Pt nanodendrites

Pt monolayer on
non-PGM cores
Pt hollow shell
Pt shell alloys

Core/shell
nanoparticles

Porous metal membranes

Nanoporous ultrathin metal lear
Vacuum-deposited
porous films
Electrodeposited films

Nanoparticles on oxide
support

Thin films on high-aspect-ratio
support particles
Thin-film-coated multi-walled and single-walled
carbon nanotubes, buckypaper

Pt nanoparticles on
oxides on carbon

Nanoparticles on
oxide support
particles

Thin-film-coated carbon papers, cloths
Thin films on polymer fibres
Thin films on inorganic, ceramic flbres and pillars
Thin films on nanostructured crystalline
organic whisker supports (NSTF catalysts)

FIGURE 9.3 Basic platinum-based heterogeneous electrocatalyst approaches. Source : Reproduced with permission from Debe [26].