Vajo John J, Skeith Sky L, Mertens Florian
J Phys Chem B. 2005 Mar 10;109(9):3719-22. doi: 10.1021/jp040769o.
Destabilization of LiBH4 for reversible hydrogen storage has been studied using MgH2 as a destabilizing additive. Mechanically milled mixtures of LiBH4 + (1/2)MgH2 or LiH + (1/2)MgB2 including 2-3 mol % TiCl3 are shown to reversibly store 8-10 wt % hydrogen. Variation of the equilibrium pressure obtained from isotherms measured at 315-400 degrees C indicate that addition of MgH2 lowers the hydrogenation/dehydrogenation enthalpy by 25 kJ/(mol of H2) compared with pure LiBH4. Formation of MgB2 upon dehydrogenation stabilizes the dehydrogenated state and, thereby, destabilizes the LiBH4. Extrapolation of the isotherm data yields a predicted equilibrium pressure of 1 bar at approximately 225 degrees C. However, the kinetics were too slow for direct measurements at these temperatures.
以MgH₂作为去稳定添加剂，对用于可逆储氢的LiBH₄的去稳定化进行了研究。机械研磨的LiBH₄ + (1/2)MgH₂或LiH + (1/2)MgB₂混合物（包含2 - 3 mol%的TiCl₃）显示出能够可逆地储存8 - 10 wt%的氢。在315 - 400℃下测量的等温线所得到的平衡压力变化表明，与纯LiBH₄相比，添加MgH₂使氢化/脱氢焓降低了25 kJ/（每摩尔H₂）。脱氢时形成MgB₂使脱氢态稳定，从而使LiBH₄不稳定。等温线数据的外推得出在约225℃时预测的平衡压力为1 bar。然而，在这些温度下动力学太慢，无法进行直接测量。
