Nano Crystalline Porous Thin Film Hydrogen Storages

Abstract

Submit Manuscript | http://medcraveonline.com as solid state hydrogen storages. V-H system includes the following phases: αsolid solution; β-(VH0.45VH0.95) with bodycentered tetragonal lattice (bct) and γ-VH2 with fcc lattice. There are three phases in Ti-H system also: α-solid solution; β-(TiH0.5-TiH0.9) with bcc-lattice and δ – TiH2 with fcc-lattice. The total mass of stored hydrogen in γ-VH2 approaches value of 2.1 wt.%. δ -TiH2 absorbs 4.0 wt.% H2. Therefore, the amount of absorbed hydrogen atoms comes to be 11.2 in VH2 is and 9.1 in TiH2 (at/cm3, x1022). In order to meet the U.S. Department of Energy (DOE) requirements [1] (gravimetric capacitance: >5.4wt%; hydrogen release temperature range: < 85°C: the time period required to achieve the maximum hydrogen flux: 4 seconds; the equilibrium pressure: < 0.4 MPa), it is necessary to solve several challenging problems: