Hydrogen is clean energy with high energy density, large-scale storage, and easy hydrogen/electricity/thermal conversion. Therefore, it has received extensive attention as an efficient and clean secondary renewable energy. The development and utilization of hydrogen energy mainly include four aspects: hydrogen production, application, storage, and transportation. The production and application technology of hydrogen is mature enough, but its storage is very inconvenient. Therefore, people need to consider the safety, high efficiency, and no leakage loss of hydrogen in storage. Appropriate materials for hydrogen storage are very important.
- The gaseous hydrogen storage technology realizes the storage of hydrogen through high pressure, which is to compress the hydrogen in a high-pressure container, which has high requirements on the material of the high-pressure container itself. The key to gaseous hydrogen storage is whether a hydrogen storage container with good performance and high safety can be developed.
- Liquid hydrogen storage technology uses cryogenic technology to store liquefied hydrogen in a container. The advantages of this technology are a large amount of hydrogen storage, the small volume of the hydrogen storage container, and the high volume density of liquid hydrogen. It is currently difficult to achieve large-scale applications.
- Solid hydrogen storage technology realizes hydrogen storage by combining hydrogen with hydrogen storage materials by physical or chemical means, which can effectively improve the shortcomings of gaseous storage and liquid storage. The advantages are high hydrogen storage density, high safety, and convenient transportation. The hydrogen storage density is about 1000 times that of gaseous hydrogen storage under the same temperature and pressure conditions, and the hydrogen absorption and desorption rate are suitable. The disadvantage is that the theoretical research and development are not perfect.
Materials for Hydrogen Storage with good performance discovered in recent years mainly include carbon-based hydrogen storage materials, organic framework hydrogen storage materials, metal hydride hydrogen storage materials, liquid organic hydride hydrogen storage materials, and other solid hydrogen storage materials.