A research group at Tohoku University has succeeded in synthesizing "a new group of substances in which as many as nine hydrogens are bonded to one metal atom."This is the result of joint research with the National Institutes for Quantum and Radiological Science and Technology, the High Energy Accelerator Research Organization, and Toyota Central R & D Labs., Inc.
In metals, there is an element group (= hydride gap) that is difficult to bond with hydrogen by itself.On the other hand, these elements can be combined with a large amount of hydrogen by forming a "complex hydride".However, although chromium and its companions molybdenum and tungsten belong to the hydride gap, it has been said that they do not bind to hydrogen even if they become complex hydrides.In contrast, in 2015, the research group discovered that it was possible to synthesize complex hydrides in which chromium and hydrogen were bound, with the exception that chromium binds to seven hydrogens, which are more than common metals. ..
This time, the research group worked on the synthesis of complex hydrides containing the remaining exceptions, molybdenum and tungsten, and the four elements of niobium and tantalum, for which no synthesis of complex hydrides has been reported so far.Specifically, by fusing theoretical calculation and high-pressure synthesis technology and optimizing the synthesis conditions, four new substance groups containing these elements were synthesized.Then, using a quantum beam such as a neutron, it was confirmed that as many as nine hydrogens were bonded to one metal.With this result, the technology to bond most metal elements and hydrogen has been established.
Substances containing high density of hydrogen have been attracting a lot of attention in recent years because they are expected to be applied as hydrogen storage materials, high-speed ion conduction materials, and superconducting materials.The results of this research are considered to be important results for expanding the search for substances containing high density hydrogen and their basic and applied research.
