HYDROGEN PERMEATION THROUGH A BILAYER OF FE ELECTRODEPOSITED NI

Hydrogen permeation through Ni coated onto Fe substrate has been investigated at room temperature by electrochemical method. Time-lag methods have been presented to describe hydrogen permeation through an Fe/electrodeposited Ni composite. The diffusivity of hydrogen in the electrodeposited Ni was determined from the time-lag equations. The results obtained under galvanostatic boundary condition agreed well with those obtained under potentiostatic boundary condition. The diffusivity of hydrogen in the electrodeposited Ni increased with increase of the Ni electrodeposit thickness. Also the steady-state hydrogen permeation flux across the composite increased slightly and nonlinearly with increasing reciprocal thickness of the electrodeposit in the range of 1–50 µm for both boundary conditions. The behavior of hydrogen permeation through the composite is discussed as related to the barrier effect of the electrodeposit and also to the hydrogen trapping by micropores present in the electrodeposit. © 1990, The Electrochemical Society, Inc. All rights reserved.