Stability of Y2O3 hydrogen isotope permeation barriers in hydrogen at high temperatures

Hydrogen isotope permeation barriers (HIPB) have great potential applications in the fields of hydrogen energy and thermonuclear fusion energy. Here, we report the stability of Y2O3 HIPB in gaseous hydrogen at high temperatures including the structures, mechanical properties and electrical properties. With increasing hydrogen treatment time at 700 °C, the high-index diffractions of Y2O3 became weak gradually whereas the (400) diffraction was strengthened. The color of the Y2O3 HIPB changed from brown to gray. The bonding strength decreased by 61% with increasing hydrogen treatment time, and finally remained unchanged. Meanwhile, the electrical resistivity of the Y2O3 HIPB decreased from 8.2 × 109 Ω cm by over two orders of magnitude and then tended to be constant. The oxygen loss as well as hydrogen incorporation was proposed to be responsible for these modifications and indications of the present work for preparation of HIPB with high reliability were discussed.

► The stability of Y2O3 HIPB in hydrogen at high temperatures was reported. ► An unusual re-orientation of the Y2O3 HIPB was observed at high temperatures. ► Electrical and mechanical properties were modified upon hydrogen treatments. ► These deteriorations were ascribed to the oxygen loss and hydrogen incorporation.