Core-shell NaBH4@Ni Nanoarchitectures: A Platform for Tunable Hydrogen Storage

The core-shell approach has surfaced as an attractive strategy to make complex hydrides reversible for hydrogen storage; however, no synthetic method exists for taking advantage of this approach. Here, a detailed investigation was undertaken to effectively design freestanding core-shell NaBH4@Ni nanoarchitectures and correlate their hydrogen properties with structure and chemical composition. It was shown that the Ni shell growth on the surface of NaBH4 particles could be kinetically and thermodynamically controlled. The latter led to varied hydrogen properties. Near-edge X-ray absorption fine structure analysis confirmed that control over the Ni-0/NixBy concentrations upon Ni-II reduction led to a destabilized hydride system. Hydrogen release from the sphere, cube, and bar-like core-shell nanoarchitectures occurred at around 50, 90, and 95 degrees C, respectively, compared to the bulk (>500 degrees C). This core-shell approach, when extended to other hydrides, could open new avenues to decipher structure-property correlation in hydrogen storage/generation.

Automated summary

The core-shell approach provides a strategy to make complex hydrides reversible for hydrogen storage. The study designed freestanding core-shell NaBH4@Ni nanoarchitectures and investigated their hydrogen properties. The core-shell nanoarchitectures exhibited lower hydrogen release temperatures compared to bulk materials, suggesting potential catalytic applications.