Improved dehydrogenation of LiAlH4 by hollow 3D flower-like bimetallic composites M-NC@TiO2 (M=Ni, Co, Fe, Cu)

The sluggish kinetics and thermodynamic stability associated with LiAlH4 4 have posed significant obstacles to its practical application. Herein, we have designed a general method for preparing a series of hollow 3D flower-like composite, denoted as M-NC@TiO2 2 (M = Ni, Co, Fe, Cu), which serve as highly efficient catalysts for the dehydrogenation of LiAlH4. 4 . These composites feature TiO2 2 hollow spheres as substrates to induce the growth of MOF nanosheets, leading to the regular arrangement of carbon nanosheets anchored with metal nanoparticles M on the TiO2 2 sphere surface after calcination treatment. Evidently, M-NC@TiO2 2 exerts a discernible enhancement on the dehydrogenation kinetics of LiAlH4. 4 . LiAlH4-7wt% 4-7wt% Ni-NC@TiO2 2 system begins to release hydrogen at a notably lowered temperature of 56.3 degrees C, with a total amount of hydrogen released of 7.19 wt% before reaching 300 degrees C. Subsequent investigations showed that the enhanced hydrogen storage performance can be attributable to the in-situ formation of the metal compounds, the fine size and high dispersion of metallic nanoparticles, and the synergistic effect between TiO2 2 and M nanoparticles. This work not only provides an effective general way to synthesize catalysts for improving the hydrogen storage performance of aluminum-based hydrogen storage materials, but also augments our understanding of hydrogen storage mechanisms.