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LiNH2 hydrogen storage volume, low price, light weight, and is considered to be one of the most promising hydrogen storage materials. LiNH2 system, however, suction and discharge high temperature hydrogen, and hydrogen absorption rate is relatively slow limiting its practical applications. The thermodynamic and kinetic properties of the hydrogen absorption and desorption to improve LiNH2 poor people in experiments done a lot Modification and achieved certain academic achievements, but less in theoretical mechanisms of hydrogen desorption performance. Committed to LiNH2 the development of practical applications of hydrogen storage materials, the papers selected LiNH2 as research subjects, relying the LiNH2 modified experimental results as the background, the establishment of a substitutional solid solution heat, heat of formation of H atoms in solution from the microscopic physical quantities with the macroscopic properties of the corresponding relationship of the stability of the phase structure of the alloy system, the solution hydrogen performance, obtained by first-principles calculation method LiNH2 microscopic physical feature amount and a variety of electronic structure information, the basic physical properties in the study LiNH2 Solution Characteristics of hydrogen on the basis of Mg, Al, Ti, Nb atoms replacement of Li LiNH2 system to examine the influence of the alloying effect on the system Solutions hydrogen performance LiNH2 system the catalytic mechanism of the discharge of hydrogen theoretically discussed based on the analysis of the electronic mechanism. Calculated LiNH2 equilibrium lattice constant, the alloy forming the heat, the electronic density of states (DOS), the electron density and the H atom dissociation energy, found that the equilibrium lattice constant, heat of formation with other calculated values, the experimental values ??better ; LiNH2 heat of formation is negative, the negative alloy to form a larger heat value, more difficult hydrogen LiNH2 Solutions; LiNH2 alloy system, Li-NH bond is mainly based on the presence of an ionic bond, NH bond is mainly based on the presence of covalently , NH strong bonding effect is LiNH2 difficult one of the main reasons of the solution of hydrogen; LiNH2 and LiH mixture system easy solution of hydrogen than Li2NH and LiH mixtures. Calculation of Mg, Al, Ti, Nb, and replacement of Li in the substitutional solid solution of the alloying system LiNH2 system heat, alloy formation heat, H-atom dissociation energy, the electronic density of states (DOS) and the electron density, and analysis showed that the alloying elements X (X = Mg, Ti, Nb) LiNH2 system a small amount of substitutional solid solution Nb permutation requires the maximum energy, and alloys A1 permutation requires minimum energy, the degree of substitution Difficult sequentially as Nb, Ti, Mg, Al; , before comparing, LiNH2 alloying system after the negative alloy forming a thermal reduction, indicating that the architecture stability deteriorates, alloying enhanced System Solutions hydrogen capacity; after alloying system alloy forming the absolute value of heat to reduce the turn is Nb, Ti, Mg, Al, that X (X = Mg, Al, Ti, Nb) alloyed to improve the performance of LiNH2 System Solutions hydrogen order of Al, Mg, Ti, Nb, wherein the Nb on LiNH2 System Solutions of hydrogen greatest impact, weakened solution of hydrogen alloying best solution Al LiNH2 system hydrogen capacity to improve is not obvious; X (X = Mg, Al, Ti, Nb) alloying improve the performance of the the LiNH2 system solution of hydrogen main reason is that: the alloying LiNH2 system Li with NH bond interactions.
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