HYDROGEN STORAGE MATERIAL CONTAINING METAL ORGANIC STRUCTURE

Abstract

The object of the present invention addresses a problem of providing a novel hydrogen storage material containing a metal-organic framework that can effectively store hydrogen. Hydrogen can be effectively stored by use of a hydrogen storage material containing a metal-organic framework, the metal-organic framework comprising a carboxylate ion of formula (I) and a multivalent metal ion, wherein the carboxylate ion and the multivalent metal ion are bound to each other. (In formula (I), X is an unsubstituted or substituted C2-C20 alkyl group, an unsubstituted or substituted alkenyl group, an unsubstituted or substituted alkynyl group, an unsubstituted or substituted alkoxy group, an unsubstituted or substituted alkenyloxy group, an unsubstituted or substituted alkynyloxy group, a benzyloxy group, an unsubstituted or substituted alkylsulfanyl group, an unsubstituted or substituted alkenylsulfanyl group, an unsubstituted or substituted alkynylsulfanyl group, an unsubstituted or substituted alkylamino group, an unsubstituted or substituted dialkylamino group, an unsubstituted or substituted alkenylamino group, an unsubstituted or substituted dialkenylamino group, an unsubstituted or substituted alkynylamino group, an unsubstituted or substituted dialkynylamino group, a phenyl group, a sulfanyl group or an unsubstituted or substituted alkoxycarbonyl group.)

##STR00001##

Claims

1. A hydrogen storage material containing a metal-organic framework, the metal-organic framework comprising a carboxylate ion of formula (I) and a multivalent metal ion, wherein the carboxylate ion and the multivalent metal ion are bound to each other: ##STR00010## wherein in formula (I), X is an unsubstituted or substituted C2-C20 alkyl group, an unsubstituted or substituted alkenyl group, an unsubstituted or substituted alkynyl group, an unsubstituted or substituted alkoxy group, an unsubstituted or substituted alkenyloxy group, an unsubstituted or substituted alkynyloxy group, a benzyloxy group, an unsubstituted or substituted alkylsulfanyl group, an unsubstituted or substituted alkenylsulfanyl group, an unsubstituted or substituted alkynylsulfanyl group, an unsubstituted or substituted alkylamino group, an unsubstituted or substituted dialkylamino group, an unsubstituted or substituted alkenylamino group, an unsubstituted or substituted dialkenylamino group, an unsubstituted or substituted alkynylamino group, an unsubstituted or substituted dialkynylamino group, a phenyl group, a sulfanyl group, or an unsubstituted or substituted alkoxycarbonyl group.

2. A hydrogen storage material containing a metal-organic framework, the metal-organic framework comprising: a carboxylate ion of formula (I); a multivalent metal ion; and an organic ligand containing two or more nitrogen atoms, with the proviso that the carboxylate ion of formula (I) is excluded, or an organic ligand containing a nitrogen atom and a carboxy ionic group, with the proviso that the carboxylate ion of formula (I) is excluded; wherein the carboxylate ion of formula (I) and the organic ligand are bound to the multivalent metal ion: ##STR00011## wherein in formula (I), X is an unsubstituted or substituted C2-C20 alkyl group, an unsubstituted or substituted alkenyl group, an unsubstituted or substituted alkynyl group, an unsubstituted or substituted alkoxy group, an unsubstituted or substituted alkenyloxy group, an unsubstituted or substituted alkynyloxy group, a benzyloxy group, an unsubstituted or substituted alkylsulfanyl group, an unsubstituted or substituted alkenylsulfanyl group, an unsubstituted or substituted alkynylsulfanyl group, an unsubstituted or substituted alkylamino group, an unsubstituted or substituted dialkylamino group, an unsubstituted or substituted alkenylamino group, an unsubstituted or substituted dialkenylamino group, an unsubstituted or substituted alkynylamino group, an unsubstituted or substituted dialkynylamino group, a phenyl group, a sulfanyl group, or an unsubstituted or substituted alkoxycarbonyl group.

3. The hydrogen storage material according to claim 1, wherein the multivalent metal ion is an ion of at least one metal selected from the group consisting of Groups 2 to 13 metals in the periodic table of elements.

4. The hydrogen storage material according to claim 1, wherein the multivalent metal ion is an ion of at least one metal selected from Zn, Fe, Co, Ni, Cu, Al, Zr and Mg.

5. A method for storing a hydrogen gas, comprising a step of contacting a hydrogen-containing gas with the hydrogen storage material according to claim 1 to cause the hydrogen gas to be adsorbed inside the hydrogen storage material.

6. A hydrogen storage tank filled with the hydrogen storage material according to claim 1 or provided by forming the hydrogen storage material according to any one of claim 1.

Description

EXAMPLES

[0157] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0158] The structures of carboxylic acids as the precursors of Organic ligands 1 to 14, of formula (I), used in the examples (hereinafter referred to as “Organic ligands” including the carboxylic acids as the precursors) are shown in Table 1.

[0159] Abbreviations in Table 1 denote the following meaning.

[0160] n-Pr: n-propyl group, i-Pr: isopropyl group, n-Bu: n-butyl group, Ph: phenyl group, Bn: benzyl group, Me: methyl group, Et: ethyl group, O: oxygen atom, N: nitrogen atom, H: hydrogen atom, C: carbon atom.

TABLE-US-00001 TABLE 1 (I) [00009] Organic Organic ligand ligand number number X X 1 n-Pr 8 BnO 2 i-Pr 9 n-BuNH 3 n-Bu 10 (n-Bu).sub.2NCH.sub.2 4 Ph 11 MeOC(═O) 5 n-PrO 12 MeO 6 n-BuO 13 EtO 7 i-PrO 14 Et

Production Example 1 Synthesis of Organic Ligand 3

[0161] Iodine (2.6 mmol) was added to p-di(n-butyl)benzene (26.3 mmol), and the resultant was dissolved in chloroform. Bromine (52.6 mmol) was added dropwise thereto, and the resultant was stirred for 48 hours. 20% sodium hydroxide was added thereto, and the resultant was extracted with diethyl ether. The extracted solution was dried over magnesium sulfate and filtered. The filtrate was distilled under reduced pressure to obtain 2,5-dibromo-1,4-di(n-butyl)benzene (22.8 mmol). Copper cyanide (30 mmol) was added to the obtained 2,5-dibromo-1,4-di(n-butyl)benzene (10 mmol), and the resultant was dissolved in dimethylformamide (30 mL). The solution was refluxed overnight and returned to the room temperature. Then, aqueous ammonia (100 mL) was added thereto. The precipitated solid was filtered off, and the residue was washed sufficiently with water and dissolved in chloroform. After dried over magnesium sulfate, the solution was filtered, and the filtrate was distilled under reduced pressure. The obtained crude product was recrystallized in hexane to obtain 2,5-dicyano-1,4-di(n-butyl)benzene (9.5 mmol) as a colorless solid. A 10 M sodium hydroxide aqueous solution (75 mmol) was added to the obtained 2,5-dicyano-1,4-di(n-butyl)benzene (5.0 mmol), and the resultant was dissolved in ethylene glycol (50 mL). Then the solution was refluxed overnight. After it was returned to the room temperature, water (100 mL) was added thereto, and hydrochloric acid was added thereto to adjust the pH to 1. The precipitated solid was filtered off and dried sufficiently to obtain 1.3 g (4.7 mmol) of Organic ligand 3.

Production Example 2 Synthesis of Organic Ligand 10

[0162] N-Bromosuccinimide (103 mmol) and azobisisobutyronitrile (1.72 mmol) were added to a solution of diethyl 2,5-dimethylterephthalate (42.9 mmol) in carbon tetrachloride (260 mL) and heated under reflux for 1 hour. Thereafter, the solution was subjected to hot filtration, and the filtrate returned to room temperature was distilled under reduced pressure. The obtained solid was washed with hexane to obtain diethyl 2,5-di(bromomethyl)terephthalate (34.1 mmol) as a crude product. The obtained bromomethyl form (2.45 mmol), dibutylamine (4.9 mmol) and triethylamine (4.9 mmol) were stirred in dichloromethane to obtain diethyl 2,5-bis(N,N-dibutylamino)terephthalate (2.43 mmol). 2,5-Bis(N,N-dibutylamino)terephthalate was hydrolyzed with sodium hydroxide (9.8 mmol) in ethanol and then neutralized with hydrochloric acid to obtain Organic ligand 10.

Comparative Example 1

[0163] Terephthalic acid in an amount of 166.7 mg was dissolved in 13 mL of DMF, and 0.28 mL of triethylamine was added thereto. 17 mL of a solution of 557.7 mg of zinc acetate dihydrate in DMF was added dropwise thereto. The resultant was stirred at room temperature for 2.5 hours, and the obtained solid was separated by centrifugation. The supernatant was removed, and the solid was immersed in DMF (20 mL) overnight. Thereafter, the supernatant was removed by centrifugation, and substitution was made using chloroform. The operation of immersing the solid obtained by centrifugation in chloroform (20 mL) and centrifuging the immersed solid again was repeated three times. Thereafter, the solid obtained by centrifugation was dried under vacuum at 150° C. for 5 hours to obtain Metal-organic framework A (white powder, 142.9 mg).

Comparative Example 2

[0164] DMF (50 mL) was added to 0.492 g of 2,5-dimethylterephthalic acid and 1.49 g of zinc nitrate hexahydrate and heated in an oven (reaction conditions: 120° C., 24 hours). It was returned to room temperature, and the supernatant was removed. DMF (50 mL) was added thereto, the supernatant was removed, and the solvent was replaced with chloroform. Chloroform (50 mL) was added thereto, and immersion was conducted overnight. The solid was subjected to suction filtration, and the obtained solid was dried under vacuum at 150° C. for 5 hours to obtain Metal-organic framework B (0.709 g).

Production Example 1-1

[0165] Organic ligand 4 (0.75 mmol), zinc nitrate hexahydrate (0.75 mmol), 1,4-diazabicyclo[2.2.2]octane (0.40 mmol) and DMF (15 mL) were stirred for 15 minutes at room temperature and under ultrasonication. Thereafter, the filtrate obtained by centrifugation and filtration was placed in an autoclave and heated in an oven (reaction conditions: 120° C., 48 hours). It was returned to room temperature, the supernatant was discarded, and then the crystal was washed with DMF. Thereafter, the crystal was immersed in DMF overnight. Thereafter, the supernatant was removed and replaced with chloroform. Then the crystal was immersed for 1 day. The step of removing the supernatant after centrifugation was repeated three times. The solid obtained by centrifugation and removal of the supernatant was dried under vacuum at 150° C. to obtain Metal-organic framework 1-1 as the target compound.

Production Example 1-2

[0166] Metal-organic framework 1-2 (white solid) was obtained by the same operation as in Production Example 1-1 except that Organic ligand 2 was used instead of Organic ligand 4.

Production Example 1-3

[0167] Metal-organic framework 1-3 (white solid) was obtained by the same operation as in Production Example 1-1 except that Organic ligand 7 was used instead of Organic ligand 4.

Production Example 1-4

[0168] Metal-organic framework 1-4 (colorless crystal) was obtained by the same operation as in Production Example 1-1 except that Organic ligand 13 was used instead of Organic ligand 4.

Production Example 2-1

[0169] Organic ligand 4 (0.485 mmol) was dissolved in DMF (7 mL). A solution of zinc acetate dihydrate (1.29 mmol) in DMF (9 mL) was added dropwise thereto. The resultant was stirred at room temperature for 2.5 hours, and the obtained solid was separated by centrifugation. The supernatant was removed, and the solid was immersed in DMF (20 mL) overnight. Thereafter, the supernatant was removed by centrifugation, and substitution was made using chloroform. The washing operation of immersing the solid obtained by centrifugation in chloroform (20 mL) overnight and centrifuging the immersed solid again was repeated three times. Thereafter, the solid obtained by centrifugation was dried under vacuum at 150° C. for 5 hours to obtain Metal-organic framework 2-1.

Production Example 2-2

[0170] Metal-organic framework 2-2 (white powder) was obtained by the same operation as in Production Example 2-1 except that Organic ligand 7 was used instead of Organic ligand 4.

Production Example 2-3

[0171] Metal-organic framework 2-3 (white powder) was obtained by the same operation as in Production Example 2-1 except that Organic ligand 2 was used instead of Organic ligand 4.

Production Example 2-4

[0172] Metal-organic framework 2-4 (pale purple powder) was obtained by the same operation as in Production Example 2-1 except that Organic ligand 1 was used instead of Organic ligand 4.

Production Example 2-5

[0173] Metal-organic framework 2-5 (colorless powder) was obtained by the same operation as in Production Example 2-1 except that Organic ligand 13 was used instead of Organic ligand 4.

Production Example 2-6

[0174] Metal-organic framework 2-6 (colorless powder) was obtained by the same operation as in Production Example 2-1except that Organic ligand 12 was used instead of Organic ligand 4.

Production Example 3-1

[0175] Organic ligand 7 (1.0 mmol) was dissolved in DMF (13 mL), and triethylamine (0.28 mL) was added thereto. A solution of zinc acetate dihydrate (2.5 mmol) in DMF (17 mL) was added dropwise thereto. The resultant was stirred at room temperature for 2.5 hours, and the obtained solid was separated by centrifugation. The supernatant was removed, and the solid was immersed in DMF (20 mL) overnight. Thereafter, the supernatant was removed by centrifugation, and substitution was made using chloroform. The washing operation of immersing the solid obtained by centrifugation in chloroform (20 mL) overnight and centrifuging the immersed solid again was repeated three times. Thereafter, the solid obtained by centrifugation was dried under vacuum at 150° C. for 5 hours to obtain Metal-organic framework 3-1 (white powder).

Production Example 3-2

[0176] Metal-organic framework 3-2 (white powder) was obtained by the same operation as in Production Example 3-1 except that Organic ligand 2 was used instead of Organic ligand 7.

Production Example 3-3

[0177] Metal-organic framework 3-3 (pale purple powder) was obtained by the same operation as in Production Example 3-1 except that Organic ligand 1 was used instead of Organic ligand 7.

Production Example 3-4

[0178] Metal-organic framework 3-4 (colorless powder) was obtained by the same operation as in Production Example 3-1 except that Organic ligand 13 was used instead of Organic ligand 7.

Production Example 4-1

[0179] DMF (40 mL) was added to Organic ligand 7 (1.2 mmol) and zinc nitrate hexahydrate (1.6 mmol) and stirred for 5 minutes. Triethylamine (14.4 mmol) was added dropwise thereto and stirred at room temperature for 15 minutes. After still standing for 20 minutes, the resultant was centrifuged for 10 minutes to remove the supernatant. DMF (10 mL) was added to the residue, and the resultant was centrifuged again for 10 minutes to remove the supernatant. After immersion in DMF overnight, the resultant was centrifuged for 10 minutes to remove the supernatant, and then chloroform (10 mL) was added thereto. The washing operation of immersing the solid obtained by centrifugation in chloroform (20 mL) overnight and centrifuging the immersed solid again was repeated three times. Thereafter, the solid obtained by centrifugation was dried under vacuum at 150° C. for 5 hours to obtain Metal-organic framework 4-1.

Production Example 4-2 to Production Example 4-9

[0180] Metal-organic frameworks 4-2 to 4-9 were obtained by the same operation as in Production Example 4-1 except that Organic ligands shown in Table 2 were used instead of Organic ligand 7.

TABLE-US-00002 TABLE 2 Production Example Organic ligand Property 4-1 7 4-2 8 4-3*.sup.1 5 4-4 6 4-5*.sup.2 2 White powder 4-6*.sup.2 1 White powder 4-7*.sup.2 13 Colorless powder 4-8 14 Colorless powder 4-9 3 Colorless powder *.sup.1Stirred at 120° C. for 24 hours with no triethylamine added *.sup.2Stirring time was set to 5 minutes.

Production Example 5-1

[0181] DMF (20 mL) was added to Organic ligand 7 (0.1 mmol) and zinc nitrate hexahydrate (0.3 mmol) and heated in an oven (reaction conditions: 120° C., 24 hours). It was returned to room temperature and centrifuged, and then the supernatant was removed. DMF (10 mL) was added thereto, the resultant was centrifuged, and then the solvent was removed and replaced with chloroform. Chloroform (10 mL) was added thereto, and immersion was conducted overnight. After removal of the chloroform by centrifugation, the residue was dried under vacuum at 150° C. for 5 hours to obtain Metal-organic framework 5-1.

Production Example 5-2 to Production Example 5-15

[0182] Metal-organic frameworks 5-2 to 5-15 were obtained by the same operation as in Example 5-1 except that Organic ligands and solvents shown in Table 3 below were used and the reaction was conducted under the reaction conditions shown in Table 3. The results are shown in Table 3.

TABLE-US-00003 TABLE 3 Temper- Heating Production Organic ature time Example ligand Solvent (° C.) (hrs.) Property 5-1 7 DMF 120 24 5-2 9 DMF 120 24 5-3 10 DMF 120 24 5-4 2 DEF 120 24 5-5 1 DMF 120 24 Colorless crystal 5-6 1 DEF 120 24 Colorless crystal 5-7 1 DMF 90 24 5-8 7 DEF 120 24 Light gray yellow crystal 5-9 7 DEF 90 48 Light gray yellow crystal 5-10 11 DEF 120 24 Pale yellow crystal 5-11 3 DMF 120 24 Off-white crystal 5-12 3 DEF 120 24 Pale yellow crystal 5-13 13 DEF 120 24 5-14 14 DMF 120 48 Pale orange crystal 5-15 14 DEF 120 24 Pale yellow crystal

Production Example 6-1

[0183] Organic ligand 1 (250 mg, 1.0 mmol), aluminum nitrate nonahydrate (750 mg, 2.0 mmol) and water (3 mL) were placed in an autoclave and heated at 200° C. for 12 hours. It was returned to room temperature and centrifuged, and then the supernatant was removed. The operation of adding DMF (10 mL), centrifuging the resultant and removing the supernatant was repeated twice. Thereafter, the operation of adding water (10 mL), centrifuging the resultant and removing the supernatant in the same manner was repeated twice. The resultant was dried under vacuum at 150° C. for hours to obtain Metal-organic framework 6-1 (brown powder, 301 mg).

Production Example 7-1

[0184] Organic ligand 1 (62.6 mg, 0.25 mmol) dissolved in ethanol (15 mL) was placed in an autoclave along with an aqueous solution (15 mL) of copper nitrate 2.5 hydrate (116 mg, 0.60 mmol) and heated at 140° C. for 24 hours. It was returned to room temperature and centrifuged, and then the supernatant was removed. The operation of adding water (10 mL), centrifuging the resultant and removing the supernatant was repeated three times. Thereafter, the operation of adding ethanol (10 mL), centrifuging the resultant and removing the supernatant in the same manner was repeated three times. The resultant was dried under vacuum at 150° C. for 5 hours to obtain Metal-organic framework 7-1 (blue powder, 47 mg).

Production Example 8-1

[0185] DMF (20 mL) and ethanol (10 mL) were added to Organic ligand 4 (63.9 mg, 0.20 mmol), zinc nitrate hexahydrate (59.8 mg, 0.20 mmol) and 4,4′-bipyridine (31.7 mg, 0.20 mmol) and stirred at room temperature for 15 minutes. The suspension was filtered through Celite, and the obtained solution was placed in an autoclave and heated at 85° C. for 48 hours. It was returned to room temperature, DMF was added thereto, and immersion was conducted overnight. Then the supernatant was removed, the solvent was replaced with chloroform, chloroform (10 mL) was added thereto, and immersion was conducted for 1 day. The operation of centrifugation, removal of the solvent, addition of chloroform again, immersion overnight, and removal of the supernatant after centrifugation was repeated three times. The solid obtained by centrifugation and removal of the supernatant was dried under vacuum at 150° C. to obtain Metal-organic framework 8-1 (51.5 mg) as the target compound.

Production Example 9-1

[0186] DMF (10 mL) and formic acid (1.8 mL) were added to Organic ligand 1 (63.2 mg, 0.25 mmol) and zirconium chloride oxide octahydrate (83.6 mg, 0.25 mmol) and heated at 120° C. for 24 hours. It was returned to room temperature, DMF was added thereto, and immersion was conducted overnight. Then the supernatant was removed, the solvent was replaced with chloroform, chloroform (10 mL) was added thereto, and immersion was conducted for 1 day. The operation of centrifugation, removal of the solvent, addition of chloroform again, immersion overnight, and removal of the supernatant after centrifugation was repeated three times. The solid obtained by centrifugation and removal of the supernatant was dried under vacuum at 150° C. to obtain Metal-organic framework 9-1 (47.1 mg) as the target compound.

Production Example 10-1

[0187] THF in an amount of 9 mL and water in an amount of 1 mL were added to 0.102 g of Organic ligand 13 and 0.233 g of nickel nitrate hexahydrate and heated in an oven (reaction conditions: 100° C., 24 hours). It was returned to room temperature, centrifuged and decanted to obtain a solid. The operation of adding DMF to the solid and centrifuging and decanting it was repeated three times. Then the solid was immersed overnight. The operation of removing the supernatant, adding chloroform to the solid, and centrifuging and decanting it was repeated three times. The solvent was replaced with chloroform, and the solid was immersed overnight. The solid obtained by decanting the solid was dried under vacuum at 150° C. for 5 hours to obtain 0.047 g of Metal-organic framework 10-1.

[0188] [Production Example 10-2] to [Production Example 10-5]

[0189] Metal-organic frameworks 10-2 to 10-5 were obtained in the same manner as in Production Example 10-1 except that Organic ligands shown in Table 4 below were used and the reaction conditions shown in Table 4 were used. The results are shown in Table 4.

TABLE-US-00004 TABLE 4 Production Organic Heating Example ligand time 10-1 13 24 Lime green crystal 10-2 7 48 Bark solid 10-3 3 48 Yellow bark powder 10-4 12 48 Yellow bark solid 10-5 2 48 Yellow powder

Production Example 11-1

[0190] 0.077 g of Organic ligand 13, 0.071 g of zirconium chloride, 0.065 g of water, 0.541 g of acetic acid and 4 mL of DMF were stirred for 5 minutes at room temperature and under ultrasonication. Thereafter, the mixture was heated in an oven (reaction conditions: 120° C., 24 hours). It was returned to room temperature, centrifuged and decanted to obtain a solid. The operation of adding DMF to the solid and centrifuging and decanting it was repeated three times. The supernatant was removed, and DMF was added thereto to immerse the solid overnight. The operation of decanting the immersed solid after centrifugation, adding acetone to the obtained solid, and centrifuging and decanting it was repeated three times. The supernatant was removed, and acetone was added thereto to immerse the solid overnight. The solid obtained by centrifugation and decantation was dried under vacuum at 150° C. for 5 hours to obtain 0.053 g of Metal-organic framework 11-1.

Production Example 11-2 to Production Example 11-5

[0191] Metal-organic frameworks 11-2 to 11-5 were obtained in the same manner as in Production Example 11-1 except that Organic ligands shown in Table 5 below were used. The results are shown in Table 5.

TABLE-US-00005 TABLE 5 Production Organic Example ligand Property 11-1 13 Colorless solid 11-2 12 Colorless powder 11-3 2 Beige solid 11-4 7 Pale green powder 11-5 1 Colorless powder

[0192] [Production Example 12-1]

[0193] Organic ligand 13 in an amount of 0.0510 g, 0.0489 g of copper nitrate trihydrate and 4 mL of DMF were added and stirred, and then the mixture was filtered. Thereafter, the mixture was heated in an oven (reaction conditions: 120° C., 24 hours). It was returned to room temperature, centrifuged and decanted to obtain a solid. The operation of adding DMF to the solid and centrifuging and decanting it was repeated three times. The supernatant was removed, and the solvent was replaced with chloroform. The operation of addition of chloroform, washing and filtration under pressure was repeated three times, and chloroform was added thereto to immerse the solid overnight. The solid was subjected to filtration under pressure, and the obtained solid was dried under vacuum at 150° C. for 5 hours to obtain 0.0488 g of Metal-organic framework 12-1.

Production Example 12-2 to Production Example 12-10

[0194] Metal-organic frameworks 12-2 to 12-10 were obtained in the same manner as in Production Example 12-1 except that Organic ligands shown in Table 6 below were used and the reaction conditions shown in Table 6 were used. The results are shown in Table 6.

TABLE-US-00006 TABLE 6 Heat- Heat- ing Production Organic ing temper- Example ligand time ature Solvent Property 12-1 13 24 120 DMF Green crystal 12-2 13 24 90 DMF Green crystal 12-3 13 24 120 DEF Green crystal 12-4 13 24 90 DEF Green crystal 12-5 7 24 120 DMF Emerald green crystal 12-6 7 24 90 DMF Emerald green crystal 12-7 7 24 120 DEF Emerald green crystal 12-8 7 24 90 DEF Emerald green crystal 12-9 3 43 120 DMF Light blue powder 12-10 3 43 90 DMF Light blue powder

Example 1

[0195] (Measurement of BET Specific Surface Area and Measurement of hydrogen Storage Capacity)

[0196] The BET specific surface area and the hydrogen storage capacity at 77 K and atmospheric pressure were measured for some of Metal-organic frameworks obtained.

[0197] The BET specific surface area and the hydrogen storage capacity at 77 K and atmospheric pressure were measured with a gas adsorption measurement device, Tristar-II (manufactured by Micromeritics Instrument Corporation)

[0198] The BET specific surface area was calculated according to the following procedure. About 50 mg of each of Metal-organic frameworks was placed inside a glass cell. The pressure inside the glass cell was reduced to vacuum at a temperature of 135° C. and the inside of the glass cell was dried for 6 hours. The glass cell was attached to the gas adsorption measurement device and immersed in a temperature-controlled bath containing liquid nitrogen. The pressure of nitrogen contained in the glass cell was gradually increased. The measurement was carried out until the pressure of nitrogen introduced into the glass cell reached 1.0×10.sup.5 Pa.

[0199] The hydrogen storage capacity at 77K and a normal pressure was calculated according to the following procedure. After the measurement for nitrogen, the gas type was changed to hydrogen to carry out the measurement. The pressure of hydrogen contained in the glass cell was gradually increased. The measurement was carried out until the pressure of hydrogen introduced into the glass cell reached 1.0×10.sup.5 Pa.

[0200] The results of the BET specific surface areas measured were shown in Table 7.

[0201] The hydrogen storage capacities measured at 77 K and atmospheric pressure are shown in Table 8.

TABLE-US-00007 TABLE 7 Metal- organic BET specific framework surface area number (m.sup.2/g) 2-2 1160 2-3 1688 2-4 1470 2-5 1389 2-6 1194 3-1 1319 3-2 1007 3-3 3789 3-4 1082 4-1 517 4-5 1485 4-6 1738 4-7 555 4-8 1907 4-9 1035 5-1 518 5-4 574 5-5 1671 5-6 1665 5-7 1640 5-8 1033 5-9 1105 5-11 1384 5-12 1306 5-14 2094 5-15 2056 9-1 433 11-1 444 11-2 698 11-4 432 11-5 508 B 426

TABLE-US-00008 TABLE 8 Metal- Hydrogen organic storage framework capacity number wt % 2-2 1.299 2-3 1.706 2-5 1.448 2-6 1.237 3-1 1.448 3-3 3.240 3-4 1.235 4-5 1.546 4-6 1.542 4-8 1.57 5-5 1.43 5-6 1.46 5-7 1.188 5-8 1.181 5-9 1.295 5-11 1.31 5-12 1.23 5-14 1.58 5-15 1.61 11-2 1.161 A 1.111

INDUSTRIAL APPLICABILITY

[0202] The hydrogen storage material of the present invention can store hydrogen at a practical level. Consequently, the metal-organic framework can make hydrogen to be utilized more easily, toward the advent of a hydrogen energy-based society.