Destabilized and catalyzed borohydride for reversible hydrogen storage
View Patent ↗A process of forming a hydrogen storage material, including the steps of: providing a first material of the formula M(BH 4 ) X , where M is an alkali metal or an alkali earth metal, providing a second material selected from M(AlH 4 ) x , a mixture of M(AlH 4 ) x and MCl x , a mixture of MCl x and Al, a mixture of MCl x and AlH 3 , a mixture of MH x and Al, Al, and AlH 3 . The first and second materials are combined at an elevated temperature and at an elevated hydrogen pressure for a time period forming a third material having a lower hydrogen release temperature than the first material and a higher hydrogen gravimetric density than the second material.
1. A process of forming a hydrogen storage material comprising the steps of:
providing a first material of the formula: M(BH 4 ) x where M is an alkali metal or an alkaline earth metal and 1≦x≦2;
providing a second material selected from:
M(AlH 4 ) x where 1≦x≦2,
a mixture of M(AlH 4 ) x 1≦x≦2 and MCl x where 1≦x≦4,
a mixture of MCl x where 1≦x≦4 and Al,
a mixture of MCl x where 1≦x≦4 and AlH 3 ,
a mixture of MH x where 1≦x≦2 and Al or AlH 3 ,
Al, and
AlH 3 ;
combining the first and second materials at an elevated temperature and at an elevated hydrogen pressure for a time period forming a third material having a lower hydrogen release temperature than the first material wherein the third material includes a partially substituted borohydride metal cation with another metal cation, or partially substituted borohydride boron with a metal, or a partially substituted cation and boron in the borohydride.
2. The process of claim 1 wherein the third material has a higher hydrogen gravimetric density than the second material.
3. The process of claim 1 including the step of ball milling the first and second materials prior to the step combining the first and second materials.
4. The process of claim 3 wherein the first and second materials are milled to a particle size of from about 50 to 100 nanometers.
5. The process of claim 1 wherein the third material reversibly stores hydrogen.
6. The process of claim 1 wherein when the third material is rehydrided, the third material thereafter reversibly releases at least about 6 wt % hydrogen.
7. The process of claim 1 wherein the first material is selected from the group consisting of: lithium borohydride, sodium borohydride, potassium borohydride, or combinations thereof.
8. The process of claim 1 wherein the alkaline earth metal is selected from the group consisting of: magnesium, calcium, strontium, barium, aluminum, and mixtures thereof.
9. The process of claim 1 wherein MCl x is selected from the group consisting of MgCl 2 , CaCl 2 , SrCl 2 , BaCl 3 , ZrCl 4 , TiCl 3 and combinations thereof.
10. The process of claim 1 wherein MH x is selected from the group consisting of MgH 2 , CaH 2 , TiH 2 , ZrH 2 and combinations thereof.
11. The process of claim 1 wherein M(AlH 4 ) x is selected from the group consisting of LiAlH 4 , NaAlH 4 , and Mg(AlH 4 ) 2 .
12. A process of forming a hydrogen storage material comprising the steps of:
providing a first material of the formula: M(BH 4 ) x where M is an alkali metal or an alkaline earth metal and 1≦x≦2;
providing a second material selected from: M(AlH 4 ) x where 1≦x≦2, a mixture of M(AlH 4 ) x and MCl x where 1≦x≦4, a mixture of MCl x where 1≦x≦4 and Al, a mixture of MCl x where 1≦x≦4 and AlH 3 , a mixture of MH x where 1≦x≦2 and Al or AlH 3 , Al, and AlH 3 ;
combining the first and second materials at an elevated temperature and at an elevated hydrogen pressure for a time period forming a third material wherein the third material reversibly stores hydrogen and wherein the third material includes a partially substituted borohydride metal cation with another metal cation, or partially substituted borohydride boron with a metal, or a partially substituted cation and boron in the borohydride.
13. A process of forming a hydrogen storage material comprising the steps of:
providing a first material of the formula: M(BH 4 ) x where M is an alkali metal or an alkaline earth metal and 1≦x≦2;
providing a second material selected from: M(AlH 4 ) x where 1≦x≦2, a mixture of M(AlH 4 ) x 1≦x≦2 and MCl x where 1≦x≦4, a mixture of MCl x where 1≦x≦4 and Al, a mixture of MCl x where 1≦x≦4 and AlH 3 , a mixture of MH x where 1≦x≦2 and Al or AlH 3 , Al, and AlH 3 ;
combining the first and second materials at an elevated temperature and at an elevated hydrogen pressure for a time period forming a third material having a lower hydrogen release temperature than the first material and a higher hydrogen gravimetric density than the second material and wherein the third material includes a partially substituted borohydride metal cation with another metal cation, or partially substituted borohydride boron with a metal, or a partially substituted cation and boron in the borohydride.