Lithium functionalized heteroborospherene Si4B32 as a promising hydrogen storage material:A density functional theory study

Abstract

This study investigates the reversible hydrogen storage performance of Lithium (Li)-functionalized heteroborospherene Si4B32 with density functional theory (DFT) methods. The Si4B32 cage can accommodate a maximum of 6Li atoms without clustering, every Li atom can bind up to 4 H2 molecules. The Li6Si4B32 can still keep its integrity after absorbing 24 H2 molecules. The H2 gravimetric density is 8.922 wt% with 0.220 eV/H2 average hydrogen adsorption energy. The desorption temperature of Li6Si4B32.(H2)24 is 281 K, which indicate H2 molecules can be successfully released at near room temperature. We draw a conclusion that Li-decorated Si4B32 is a potential candidate for reversible hydrogen storage.