Hydrogen-Accumulating Materials Based on Titanium and Iron Alloys (Review)

The development of compact, safe, and efficient methods for storing hydrogen is one of the key problems of hydrogen energy. Currently used technologies for storing hydrogen in the form of compressed gas or cryogenic liquid require significant capital investments and maintenance costs for compressor and cryogenic equipment, are characterized by high energy costs, and their implementation requires special safety measures as well as the use of hydrogen-neutral structural materials. A promising way to solve these problems for medium-scale storage systems is the use of metal hydrides, which provide the simplest, most compact, and safe hydrogen storage compared to traditional methods. However, the high cost of hydride-forming materials hinders the implementation of this approach. The use of alloys based on the TiFe intermetallic compound would reduce the costs of metal hydride hydrogen storage by more than five times. This circumstance is the reason for the growing interest of specialists in the field of hydrogen energy technologies in hydrogen-storage materials based on titanium-iron alloys. Although hydrogen systems with the TiFe intermetallic compound and its derivatives have been studied for more than 50 years, the search for ways to increase the resistance of their hydrogen sorption characteristics to poisoning by oxygen-containing impurities in the gas and solid phases has become particularly relevant in recent years. This article provides an overview of research and development aimed at obtaining, studying the properties, and using titanium-iron alloys with improved hydrogen sorption characteristics. An analysis of the data presented in the scientific literature is presented, and approaches to the development of highly efficient hydride-forming materials based on the TiFe intermetallic compound and hydrogen-storage systems based on them are formulated.