Extensive research is underway worldwide to employ hydrogen as a clean energy source that does not exhaust carbon dioxide. However, for practical use as a future energy source, three kinds of technical developments are required: production of hydrogen, storage of hydrogen, and hydrogen fuel cell which converts hydrogen energy to electric energy. In order to convert various vehicles, which use gasoline or light-oil to those using hydrogen energy, a technique for storing hydrogen which stores a large amount of hydrogen in a safe and convenient manner and enables loading hydrogen on the vehicles is absolutely required.
An organic-transition metal complex which can safely and reversibly store hydrogen in a high capacity has been manufactured by Korean researchers from Seoul National University Industry Foundation (Seoul, KR), Hanwha Chemical Corporation (Seoul, KR) and Industry-University Cooperation Foundation Hanyang University (Seoul, KR). The materials are variations of titanium (IV) hydride phenoxide such as 1,4-bis(trichlorotitanium)phenoxide) and bis(titanium (IV) hydride)ethoxide,
Inventors Jisoon Ihm, Hoonkyung Lee, Hyo Jin Jeon, Jong Sik Kim, Dong Ok Kim, Hee bock Yoon, Jeasung Park, Seong-Geun Oh, and Chul Oh describe the process for preparing the organometallic complexes in U.S. Patent Application 20100022791. The organic-transition metal hydride complex can be produced in a stable manner with good yield. The organometallic complex is prepared from the bonding of a hydroxyl-containing organic substance with a transition metal compound.
The hydrogen storage material comprises a complex generated by combination of an organic substance containing a hydroxyl (--OH) group(s) with a transition metal containing compound, which can more effectively store hydrogen with more than one transition metal being bonded per molecule. Examples of the organic substances containing hydroxyl (--OH) group(s) include alkyl derivatives such as ethylene glycol, trimethylene glycol and glycerol, and hydroxyl-containing aryl derivatives such as fluoroglucinol. As the transition metal, titanium (Ti), vanadium (V) and scandium (Sc), which can make Kubas binding, may be mentioned.
The hydrogen storage material can be used under mild conditions (for example, for storage at 25 degree C, 30 atm; for release at 100 degree C under 2 atm) as compared to conventional storage material. The material can dramatically increase the storage amount of hydrogen. In addition, the organic-transition metal complex hydrogen storage material enables a large capacity of hydrogen storage in a safe and reversible manner
The organometallic hydride complex as hydrogen storage material can store and use under a condition approximate to ambient temperature and ambient pressure via Kubas binding between transition metal and hydrogen. In addition, the complex can bind multiple transition metals per molecule since it utilize hydroxyl group as a reactive group, so that excellent weight percentage of stored hydrogen per total material suggested as hydrogen storage material, and weight of hydrogen per unit volume are expected.