The pressure, and lattice parameter, dependences of H diffusion in NbH0.002 were studied at 187K by using neutron spectroscopic techniques. The diffusivity at 187K and 1bar was equal to 8.6 x 10-7cm2/s. It was found that a pressure of 5kbar reduced the lattice parameter by about 0.1% and decreased the diffusion coefficient by about 3.4%. This pressure dependence was much smaller than that of H diffusion in Pd at room temperature.

Lattice-Parameter Dependence of the Diffusivity of Hydrogen in Niobium. U.Stuhr, H.Wipf, C.Vettler, H.R.Schober: Solid State Communications, 1991, 80[12], 987-9

 

Table 93

Parameters for H Diffusion in Nb at Temperatures above 165K

 

O (at%)

N (at%)

C (at%)

H (at%)

Method

Do (cm2/s)

E(eV)

0.14

0.06

<0.01

2.2

dynamic

2.8 x 10-4

0.089

0.08

0.02

<0.01

1.6

dynamic

2.8 x 10-4

0.089

0.23

0.005

0.006

0.28

static

2.4 x 10-4

0.096

0.043

0.006

0.005

0.095

static

1.7 x 10-4

0.081

0.029

0.009

0.005

0.11

static

1.6 x 10-4

0.080