  Developing applicable two-dimensional (2D) electrode materials with high
performance, especially with high ion storage capacity, has become an ever more
obsessive quest in recent years. Based on first-principles calculations, we
report that T-graphene, a new carbon-based 2D material, has a record-high Li/Na
storage capacity. The capacity of T-graphene is as high as 2233.2 mA h g-1 for
Li, and can reach 2357.2 mA h g-1 for Na, which are 6 times as much as that of
the commercial graphite and are the highest among 2D anode materials identified
so far. We demonstrate that the ultrahigh storage capacity of T-graphene mostly
benefits from its low atomic mass and special periodic lattice structure.
T-graphene has not only the ultrahigh storage capacity but also hosts the
stable ion adsorption, good electric conductivity, fast ion diffusion speed,
and low open-circuit voltage, which are merits required as a superior anode
material for Li-ion and Na-ion batteries with ultrahigh storage capacity.
