A novel hydrogen storage system of KLi3(NH2)4-4LiH with superior cycling stability

• Hydrogen storage properties of the KLi3(NH2)4-4LiH system was first examined.
• The KLi3(NH2)4-4LiH system exhibits a superior cycling stability.
• Mixing of potassium cations into LiNH2 can result in destabilization of LiNH2.
• Dehydrogenation kinetics of the Li–N–H system is improved by mixing potassium.

In this study, we first examined the hydrogen release, uptake, and reversibility properties of the KLi3(NH2)4-4LiH system and elucidated the influence of potassium cations' substitution into LiNH2 on the hydrogen storage properties of the LiNH2-LiH composite. Our results show that mixing of the potassium cations into LiNH2 can destabilize LiNH2, therefore decreasing the hydrogen desorption temperature and enhancing hydrogen desorption rate of the LiNH2-LiH system. Notably, the KLi3(NH2)4-4LiH composite exhibits a superior cycling stability compared with the LiNH2-LiH composite prepared under the same condition.