Changeover of the Thermodynamic Behavior for Hydrogen Storage in Rh with Increasing Nanoparticle Size
The author first reports the hydrogen storage properties of Rh nanoparticles having a diameter over 10 nm and the change in the temperature dependences of hydrogen storage based on particle sizes of Rh nanoparticles. Hydrogen storage was investigated by hydrogen pressure-composition isotherm and solid-state 2H NMR measurements. The author demonstrates that Rh nanoparticles with dimensions of ~10 nm absorb hydrogen similar to smaller Rh nanoparticles, however the enthalpy of hydrogen storage in Rh nanoparticles is changed from exothermic to endothermic with increasing particle size, with a critical size between 7.1 and 10.5 nm. The thermodynamics of hydrogen storage in Rh can be tuned by controlling the particle size.
KeywordsHydrogen Absorption Hydrogen Storage Increase Particle Size Hydrogen Storage Material Hydrogen Storage Property
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