High capacity stabilized complex hydrides for hydrogen storage
View Patent ↗Complex hydrides based on Al(BH 4 ) 3 are stabilized by the presence of one or more additional metal elements or organic adducts to provide high capacity hydrogen storage material.
1. A hydrogen storage composition, comprising:
a complex compound having the composition
M x+ Al 3+ (BH 4 − ) 3+x ,
wherein
M is a metal other than Al selected from the group consisting of alkali metals, alkaline earth metals, transition metals and lanthanide rare earth elements;
x is a valence number of 1, 2, 3, 4, 5, 6, 7 or 8,
the complex compound is a solid material, and
the hydrogen storage composition is capable of releasing hydrogen at a temperature of less than 200° C.
2. The hydrogen storage composition according to claim 1 , wherein M is an alkali metal.
3. The hydrogen storage composition according to claim 2 , wherein
M is selected from the group consisting of Li, Na and K; and x is 1.
4. The hydrogen storage composition according to claim 1 , wherein M is an alkaline earth metal.
5. The hydrogen storage composition according to claim 4 , wherein
the M is selected from the group consisting of Mg, Ca, Sr and Ba; and
x is 2.
6. A method to prepare a hydrogen storage composition, the method comprising:
reacting Al(BH 4 ) 3 with a stabilization agent to obtain
a complex compound having the composition
M x+ Al 3+ (BH 4 − ) 3+x ,
wherein
M is a metal other than Al selected from the group consisting of alkali metals, alkaline earth metals, transition metals and lanthanide rare earth elements;
x is a valence number of 1, 2, 3, 4, 5, 6, 7 or 8,
the complex compound is a solid material, and
the hydrogen storage composition is capable of releasing hydrogen at a temperature of less than 200° C.
7. The method according to claim 6 , wherein
the Al(BH 4 ) 3 is unsolvated Al(BH 4 ) 3 ; and
the unsolvated Al(BH 4 ) 3 is synthesized by reacting AlCl 3 with LiBH 4 in an inert environment.
8. The method according to claim 6 , wherein
the Al(BH 4 ) 3 is solvated Al(BH 4 ) 3 ; and
the solvated Al(BH 4 ) 3 is synthesized by reacting AlCl 3 with LiBH 4 in an aprotic solvent.
9. A hydrogen storage composition, comprising:
a complex compound having the composition
M1 x+ M2 y+ Al 3+ (BH 4 − ) 3+x+y ,
wherein
M1 and M2 are different metals other than Al selected from the group consisting of alkali metals, alkaline earth metals, transition metals and lanthanide rare earth elements;
x is a valence number of 1, 2, 3, 4, 5, 6, 7 or 8;
y is a valence number of 1, 2, 3, 4, 5, 6, 7 or 8
the complex compound is a solid material, and
the hydrogen storage composition is capable of releasing hydrogen at a temperature of less than 200° C.
10. The hydrogen storage composition according to claim 9 , wherein M1 and M2 are different metals selected from the group consisting of alkali metals.
11. The hydrogen storage composition according to claim 10 , wherein
metals M1 and M2 are selected from the group consisting of Li, Na and K;
x is 1; and
y is 1.
12. The hydrogen storage composition according to claim 9 , wherein M1 and M2 are different metals selected from the group consisting of alkaline earth metals.
13. The hydrogen storage composition according to claim 12 , wherein
the metals M1 and M2 are different metals selected from the group consisting of Mg, Ca, Sr and Ba;
x is 2; and
y is 2.
14. A method of making a hydrogen storage composition, the method comprising:
reacting Al(BH 4 ) 3 with two stabilization agents to obtain a complex compound having the composition
M1 x+ M2 y+ Al 3+ (BH 4 − ) 3+x+y ,
wherein
M1 and M2 are different metals other than Al selected from the group consisting of alkali metals, alkaline earth metals, transition metals and lanthanide rare earth elements;
x is a valence number of 1, 2, 3, 4, 5, 6, 7 or 8;
y is a valence number of 1, 2, 3, 4, 5, 6, 7 or 8
the complex compound is a solid material, and
the hydrogen storage composition is capable of releasing hydrogen at a temperature of less than 200° C.
15. A hydrogen storage composition, comprising:
a complex compound having a formula
Al(BH 4 ) 3 :R,
wherein
R is an organic adduct,
the complex compound is a solid material, and
the hydrogen storage composition is capable of releasing hydrogen at a temperature of less than 200° C.
16. The hydrogen storage composition according to claim 15 , wherein R is selected from the group consisting of amines and phosphines.
17. The hydrogen storage composition according to claim 15 , wherein R is selected from the group consisting of trimethyl amine, trimethyl phosphine and triethylene diamine.
18. A method to prepare the hydrogen storage composition of claim 15 , the method comprising
reacting Al(BH 4 ) 3 with a stabilization agent comprising an organic adduct; and
producing the complex compound of formula
Al(BH 4 ) 3 :R,
wherein
R is an organic adduct.
19. The method according to claim 18 , wherein
the Al(BH 4 ) 3 is unsolvated Al(BH 4 ) 3 ; and
the unsolvated Al(BH 4 ) 3 is synthesized by reacting AlCl 3 with LiBH 4 in an inert environment.
20. The method according to claim 18 , wherein
the Al(BH 4 ) 3 is solvated Al(BH 4 ) 3 ; and
the solvated Al(BH 4 ) 3 is synthesized by reacting AlCl 3 with LiBH 4 in an aprotic solvent.
21. A hydrogen storage composition, comprising a compound selected from the group of compounds consisting of:
a compound of the formula K[Al(BH4)4] having the XRD spectrum shown in FIG. 5 ,
a compound of the formula Li[Al(BH4)4] having the XRD spectrum shown in FIG. 6 ,
a compound of the formula Al(BH4)3.xTEDA where x=1 or 2 having the X-ray diffraction spectrum shown in FIG. 7 .