Metal

Composite number

Engineering

Chemical physics

Phenylene

Metallurgy

Materials science

Graphene

Biphenylene

Crystal structure

Carbon fibers

Chemical engineering

Physical chemistry

Polymer

Nanotechnology

Organic chemistry

Tetragonal crystal system

Composite material

Monolayer

Crystallography

Chemistry

Electrode

Anode

Physical Chemistry Chemical Physics

Allotrope metal structures composed of carbon as anode materials for metal-ion batteries are a current research hotspot. In this work, the recently synthesized graphene allotrope, two-dimensional (2D) biphenylene, consisting of tetragonal, hexagonal and octagonal carbon rings, was explored theoretically. Our first-principles calculations verified that 2D biphenylene has dynamical, mechanical and thermal stability and exhibits metallic features. Its novel structure can provide multiple adsorption sites for Na ions, a fast charge-discharge rate (low Na migration barriers of <0.2 eV) and high theoretical capacity (1075.37 mA h g-1). These superior properties, combined with its carbon abundance and light mass, make the biphenylene monolayer a promising high-performance anode for sodium-ion batteries (SIBs).

Biphenylene monolayer: a novel nonbenzenoid carbon allotrope with potential application as an anode material for high-performance sodium-ion batteries