Hydrogen storage behavior of 2LiBH4/MgH2 composites improved by the catalysis of CoNiB nanoparticles

• 2LiBH4/MgH2 catalyzed by CoNiB nanoparticles were investigated systematically.
• The 2LiBH4/MgH2-10wt% CoNiB composite releases10.8 wt% H2 below 500 °C.
• The Ea of 2LiBH4/MgH2-10wt% CoNiB are lower than those of pure MgH2 and LiBH4.
• The catalytic mechanism of CoNiB on 2LiBH4/MgH2 is preliminarily investigated.

2LiBH4/MgH2 system is a representative and promising reactive hydride composite for hydrogen storage. However, the high desorption temperature and sluggish desorption kinetics hamper its practical application. In our present report, we successfully introduce CoNiB nanoparticles as catalysts to improve the dehydrogenation performances of the 2LiBH4/MgH2 composite. The sample with CoNiB additives shows a significant desorption property. Temperature programmed desorption (TPD) measurement demonstrates that the peak decomposition temperatures of MgH2 and LiBH4 are lowered to be 315 °C and 417 °C for the CoNiB-doped 2LiBH4/MgH2. Isothermal dehydrogenation analysis demonstrates that approximately 10.2 wt% hydrogen can be released within 360 min at 400 °C. In addition, this study gives a preliminary evidence for understanding the CoNiB catalytic mechanism of 2LiBH4/MgH2