Study on Correlation Between the Structure and Hydrogen Storage Properties of Palladium Nanoparticles

合成了钯黑和三种尺寸分别为12、20和40 nm的单晶立方钯纳米粒子，研究了其尺寸依赖的储氢/放氢性能。Pd纳米颗粒的储氢能力与Pd黑的储氢能力相同，尽管发现一旦储存在Pd纳米颗粒中的氢原子比Pd黑中的氢原子在化学上更稳定。熵变和焓变的XRD和原位测量支持上述观察。另一方面，单晶八面体Pd纳米粒子具有与Pd黑相似的储氢/放氢性能。

Palladium (Pd) black and three kinds of single crystalline cubic Pd nanoparticles with sizes of 12, 20, and 40 nm were synthesized to investigate the size-dependent hydrogen storage/release properties of the Pd nanoparticles. A hydrogen storage capacity of Pd nanoparticles is identical to that of Pd black, although it was found that the hydrogen atoms once stored in the Pd nanoparticles are thermodynamically more stable than those in the Pd black. Both entropy and enthalpy changes of hydrides and in-situ XRD measurements support the above observation. On the other hand, the single crystalline octahedral Pd nanoparticles have the similar hydrogen storage/release properties to the Pd black.