Impurity element analysis of aluminum hydride using PIXE, XPS and elemental analyzer technique

Aluminum hydride (AlH3), an attractive hydrogen storage material, plays an important role in rocket and aerospace industry. The impurities in aluminum hydride may seriously cause the deterioration in its properties and stability. Mixing AlH3 sample with the known content of silicon, we distinguish the elements in AlH3 and determine their concentration by using PIXE, XPS and elemental analyzer. Al, Si, Cl, Ca and Fe were identified by PIXE. XPS technique was used to measure the oxidized product of the mixed silicon. C, H content were obtain from the elemental analyzer. The results of the impurity concentration show the effectiveness of the synergy among these techniques except carbon. The XPS result from the pristine sample shows the concentration of carbon is 6 times larger than the major element Al while the result from the elemental analyzer is only 0.620 wt %. It suggests that the XPS technique is surface-sensitive and not well suited to the determination of the bulk concentration of carbon. The mass fraction ratio of Al to H is mu(Al/H) = 8.718 < 27/3, which indicates that the product partly decomposes.

Automated summary

The impurities in aluminum hydride can cause deterioration in its properties and stability. By using PIXE, XPS, and elemental analyzer, a study was conducted to identify elements and determine their concentration in AlH3 samples mixed with silicon. While XPS is useful for surface analysis, the elemental analyzer is more suitable for measuring bulk concentrations.