MRS Proceedings

Table of Contents - Volume  1098  - Symposium HH – The Hydrogen Economy  

Editors : B. Choudhury, A. DIllon, J. Keller, C. Moen

Articles

Microstructure and Hydrogen Absorption/Desorption Behavior of Nanoporous Pd Thin Films

2008 MRS Spring Meeting.

Wen-Chung Lia1, Simone C. Schendela2 and T. John Balka3

a1 micro_scientist@yahoo.com.tw, University of Kentucky, Chemical and Materials Engineering, 700 Woodland Ave. Apt. A-8, Lexington, KY, 40508, United States, 859-797-9539, 859-323-1929

a2 simone.schendel@googlemail.com, University of Kentucky, Chemical and Materials Engineering, 177 F. Paul Anderson Tower, Lexington, KY, 40506-0046, United States

a3 balk@engr.uky.edu, University of Kentucky, Chemical and Materials Engineering, 177 F. Paul Anderson Tower, Lexington, KY, 40506-0046, United States

Abstract

Nanoporous Pd (np-Pd) prepared from Pd-Ni alloy films on Si substrates was studied to understand hydriding/dehydriding processes in nanoscale Pd. Porous structures of the np-Pd thin films can be changed under different dealloying conditions. Stress measurement of the np-Pd showed that the np-Pd thin films can survive hydrogen pressures from 0 to 1 atm with no blistering, although this problem often occurs in dense Pd films in actual, high-pressure hydrogen environments. These tests indicated that hydrogen atoms can be stored in the np-Pd for much longer times than in fully dense Pd films subjected to ambient conditions. It is proposed that the stress distribution in np-Pd and the small pore size (<10 nm) inhibit hydrogen diffusion to free surfaces and thus prevent hydrogen degassing from the nanoporous structure. Moreover, phase transformation of Pd hydrides and effect of hydrogen trapping are also considered as possible reasons for the slow release of hydrogen.

(Received June 16 2008)

(Accepted June 16 2008)

Key Words

  • Pd;
  • nanoscale;
  • H
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