A Unique Double ‐Layered Carbon Nanobowl‐Confined Lithium Borohydride for Highly Reversible Hydrogen Storage

A double ‐layered carbon nanobowl‐confined LiBH4 composite is prepared by a facile melt infiltration process. The composite readily desorbs and absorbs ≈8.5 wt% of H2 at 300 °C and 100 bar of hydrogen pressure. The practical volumetric energy density reaches as high as 82.4 g L−1 with considerable dehydriding kinetics after cold pressing to form a pellet. AbstractPoor reversibility and high desorption temperature restricts the practical use of lithium borohydride (LiBH4) as an advanced hydrogen store. Herein, a LiBH4 composite confined in unique double ‐layered carbon nanobowls prepared by a facile melt infiltration process is demonstrated, thanks to powerful capillary effect under 100 bar of H2 pressure. The gradual formation of double ‐layered carbon nanobowls is witnessed by transmission electron microscopy (TEM) observation. Benefiting from the nanoconfinement effect and catalytic function of carbon, this composite releases hydrogen from 225 °C and peaks at 353 °C, with a hydrogen release amount up to 10.9 wt%. The peak tem perature of dehydriding is lowered by 112 °C compared with bulk LiBH4. More importantly, the composite readily desorbs and absorbs ≈8.5 wt% of H2 at 300 °C and 100 bar H2, showing a significant reversibility of hydrogen storage. Such a high reversible capacity has not ever been observed under the identical conditions. The usable volumetric energy density reaches as high as 82.4 g L−1 with considerable dehydriding kinetics. The find...

Source: Small - June 30, 2020 Category: Nanotechnology Authors: Ruyan Wu, Xin Zhang, Yongfeng Liu, Lingchao Zhang, Jianjiang Hu, Mingxia Gao, Hongge Pan Tags: Full Paper Source Type: research