In Situ Stress and Nanogravimetric Measurements During Hydrogen Adsorption/Absorption on Pd Overlayers Deposited onto (111)-Textured Au

Abstract

The stress induced by electrochemical hydrogen adsorption and absorption in very thin palladium layers electrodeposited onto (111)-textured gold has been examined in 0.1 M H2SO4 by the cantilever curvature method and by comparing resonant frequency changes on AT- and BT-cut quartz crystals. A compressive surface stress change of about −0.25 N m−1 is measured in the hydrogen adsorption region. Compressive stress for hydrogen adsorption is not expected from charge distribution models for adsorbate-induced surface stress but is consistent with first-principles calculations in the literature as well as experimental data for H adsorbed on Pt(111). Cantilever measurements in the hydrogen absorption region are consistent with a maximum atomic H/Pd loading of 0.63 and give a compressive stress-thickness change of −0.45 N m−1 per monolayer of Pd, corresponding to a biaxial stress change of −2.0 GPa. A somewhat lower value of −0.80 GPa for a H/Pd loading of 0.68 was obtained from EQNB data using the double crystal technique. These stress values fall well within the range of experimental values reported in the literature for β-hydride generated both electrochemically and from the gas phase.

In Situ Stress Measurement During Hydrogen Sorption on Ultrathin (111)-Textured Pd Films in Alkaline Electrolyte

“…The observed compressive stress is consistent with first principle calculations 44 as well as experimental data for both hydrogen on Pd (Ref. 8) and Pt (Refs. 43 and 45).…”

Stress in aluminum induced by hydrogen absorption during cathodic polarization

“…Hydrogen absorption into the Au layer is not expected, based on measurements of hydrogen absorption into Pd films on Au/Ti/glass cantilevers fabricated in the same way as those used here [11]. The deposited Al film had a strong (111) crystallographic orientation.…”

“…In situ stress measurements can provide highly sensitive methods for detection of hydrogen in thin metal films [5,[9][10][11]. Absorption of hydrogen atoms at interstitial sites in the metal produces elastic volume expansion of the lattice [12].…”

“…The measured stress change can be directly related to the quantity of absorbed hydrogen, even in the presence of gas evolution and corrosion reactions. While stress measurements have been used to study electrochemical hydrogen absorption into Pd, apparently no studies of reactive metals have been reported [11,[14][15][16].…”

In Situ Stress Measurements during Cobalt Electrodeposition on (111)-Textured Au

“…78 Even as the Co approaches monolayer coverage, the misfit strain can be relaxed by adsorbed hydrogen since the Co is known to be hydrogen terminated at these potentials. 12 Hydrogen adsorbed on both Pt 79 and Pd 80,81 show large compressive changes in surface stress. We can therefore conclude that the misfit term in Eqn.…”