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Updated: May 15, 2026
A Protocol for Safe Lithiation Reactions Using Organolithium Reagents
Published on: November 12, 2016
A novel three-step method for preparation of a TiB2-promoted LiBH4-MgH2 composite for reversible hydrogen storage
Xiangdong Kang1, Kuikui Wang, Yujie Zhong
1Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, P. R. China.
Abstract:
The reversible dehydrogenation properties of the 2LiBH(4)-MgH(2) composite can be effectively improved by incorporating heterogeneous nucleation agents, typically transition metal borides. A careful study of the 2LiBH(4)-MgH(2) composite with a titanium trifluoride (TiF(3)) additive finds that using the conventional one-step milling method renders only a partial conversion from TiF(3) to titanium boride (TiB(2)) through an intermediate of titanium hydride (TiH(2)). Based on a fundamental understanding of the reaction processes of the system, we developed a three-step preparation method, which involves pre-milling the LiBH(4)-TiF(3) mixture, isothermal treatment and milling together with MgH(2). A combination of phase/chemical state/microstructural analyses using X-ray diffraction, X-ray photoelectron spectroscopy and transmission electron microscopy techniques shows that the newly developed method can effectively promote the formation of TiB(2) and meanwhile, ensure a homogeneous dispersion of TiB(2) nanoparticles in the composite matrix. As a consequence, the composite sample prepared by the new method exhibits a favorable combination of high hydrogen capacity, fast reaction kinetics and satisfactory cyclic stability.
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