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The remarkable hydrogen de/absorption properties of lithium borohydride are achieved by mechanically milling LiBH 4 with hexagonal boron nitride (h-BN). It is found that the dehydrogenation properties of LiBH 4 are improved with increasing the amount of h-BN. The 30 mol% h-BN doped LiBH 4 composite starts to release hydrogen from just 180 C, which is 100 C lower than the onset dehydrogenation temperature of ball milled LiBH 4 . Moreover, the 30 mol% h-BN doped LiBH 4 composite can release 12.6 wt% hydrogen in 2 h at 400 C, while only 0.98 wt% H 2 is gained from ball milled LiBH 4 . The apparent activation energy (E a ) of hydrogen desorption had been reduced from 198.31 kJ mol À1 for ball milled LiBH 4 to 155.8 kJ mol À1 for 30 mol% h-BN doped LiBH 4 . In addition, the rehydrogenation of the composite is achieved under 400 C and 10 MPa of H 2 . These remarkable results are largely attributed to the lone pair electrons of nitrogen induced destabilization of LiBH 4 and their heterogeneous nucleation.

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