Molecular beam-thermal hydrogen desorption from palladium.
Among the most efficient techniques for hydrogen desorption monitoring, thermal desorption mass spectrometry is a very sensitive one, but in certain cases can give rise to uptake misleading results due to residual hydrogen partial pressure background variations. In this work one develops a novel thermal desorption variant based on the effusive molecular beam technique that represents a significant improvement in the accurate determination of hydrogen mass absorbed on a solid sample. The enhancement in the signal-to-noise ratio for trace hydrogen is on the order of 20%, and no previous calibration with a chemical standard is required. The kinetic information obtained from the hydrogen desorption mass spectra (at a constant heating rate of 1 degrees C/min) accounts for the consistency of the technique.
Lobo
R F M
RF
Grupo de Nanotecnologia e Ciência à Nano-Escala, Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, 2829-516 Caparica, Portugal. rfl@fct.unl.pt
Berardo
F M V
FM
Ribeiro
J H F
JH