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Herein, we consider the potential application of plasma immersion ion implantation (PIII) for treatment of polymer surfaces. This paper presents some experimental data for ultra-high molecular weight polyethylene (UHMWPE) implanted with nitrogen using PIII process. This polymer is widely used in medical prosthesis and PIII treatment has revealed to be an ease and cheap way to improve the lifetime of prosthesis made with UHMWPE. Here we show the latest results for UHMWPE surface treatment obtained with the use of a high voltage pulser of 100kV/200A based on coaxial Blumlein technology. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Nanocrystalline aluminum hydrides (alanates) are potential hydrogen storage materials for PEM fuel cell applications. One of candidates is magnesium alanate, Mg(AlH4)2, which contains 9.3 wt. % of hydrogen. In the present work, the effects of Ti catalyst in improving the kinetics of hydrogen uptake and release are investigated. The 2–5 μm thick MgAl films have been hydrogenated employing plasma immersion ion implantation technique as a function of Ti-content. Nanocrystalline MgAl films were prepared by magnetron sputter deposition in vacuum. Titanium atoms were incorporated simultaneously into the growing film. Morphological and structural properties were studied by scanning electron and atomic force microcopies and X-ray diffraction technique. It is shown that the microstructure of the hydrided/dehydrided MgAl film is highly defected and demonstrates dispersed/amorphous cluster-like structure. Ti atoms in MgAl film kinetically enhance the dehydrogenation of magnesium alanate film. For Ti-doped MgAl film the dehydrogenation process becomes about 1.5 times shorter and the dehydrogenation temperature about 50 K less than for Ti-undoped film for the temperature rise rate equal to 18 K-min-1. It is shown when hydrogenated MgAl film is exposed to air a compact amorphous Al2O3 layer with typically 3–5 nm thickness grows on the surface. Thin native oxide acts as a permeation barrier for hydrogen. It has been found that the major part of hydrogen effuses at ∼630 K and the effusion process is controlled by the migration of hydrogen through the surface oxide layer. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]