Electronic and structural properties of Lin @Be2 B8 (n = 1-14) and Lin @Be2 B36 (n = 1-21) nanoflakes shed light on possible anode materials for Li-based batteries.

Systematic addition of Li atoms to the Be2 B8 and Be2 B36 backbones has been studied by density functional theory-based calculations with the aim to investigate properties of interest on possible anode materials for Li-based batteries. For the Be2 B8 Lin (n = 1-8) and the Be2 B36 Lin (n = 1-20) systems, lithium salts are dominant whereas a clear electride feature shows up for Be2 B8 Lin (n = 9-14) and Be2 B36 Li21 . Addition of hydrogen radicals to these systems shows that the Be2 B8 Li14 electride becomes a Be2 B8 Li14 H2 hydride electride whereas Be2 B36 Li21 leads to a Be2 B36 Li21 H salt. Moreover, for the addition of Li atoms to Be2 B8 and the Be2 B36 backbones, large values of the interaction and of the adsorption energy per Li atom, high specific capacity of Be2 B8 Li14 and of Be2 B36 Li21 (1860 and 1017 mAh g-1 , respectively) and low and flat voltage associated with lithiation have been found. Likewise, the considerable thermodynamic driving force (ΔG° = -29.66 kcal/mol) and the small energy barrier ( ΔG# = 0.26 kcal/mol) associated with electron transfer in Be2 B36 Li21 and Be2 B36 species confirm that boron rich species have potential abilities to be used in the Li-based battery. © 2018 Wiley Periodicals, Inc.