Two-Dimensional Biphenylene-Based Carbon Allotrope Family with High Potassium Storage Ability

The development of new carbon materials with novel properties
and
excellent applications is essential and urgent in many fields, such
as potassium-ion batteries (PIBs). In this study, a family of 30 two-dimensional
biphenylene carbon allotropes (2D-BCAs) have been systematically extended
in theory. The energies of these allotropes are slightly higher than
that of graphene, which can be well described by a quantitative energy
equation. The 2D-BCAs show high synthesizability consistent with the
experimental biphenylene network via “HF-zipping” reactions.
The 2D-BCAs are metallic or semimetallic. Six representative 2D-BCAs
exhibit good lattice dynamical and thermal stability, excellent anisotropic
mechanical properties, and ORR catalytic activity. Moreover, the selected
2D-BCAs demonstrate ultrahigh theoretical potassium-storage capacities
of 1116–1489 mAh·g–1, low migration
barriers of 0.03–0.22 eV, and low open-circuit voltages of
1.10–0.02 V. The remarkable properties render 2D-BCAs as promising
anode materials in PIBs, electrocatalysts, and conductors in electronics
and iontronics.

在众多领域，如钾离子电池（PIB）等领域，开发具有新颖特性和卓越应用前景的新型碳材料显得至关重要且迫在眉睫。本研究中，一种由30种二维双苯基碳同素异形体（2D-BCAs）组成的系列在理论层面得到了系统性拓展。这些同素异形体的能量略高于石墨烯，其能量可通过定量能量方程得到良好描述。2D-BCAs表现出高度的可合成性，与实验中通过“HF-zipping”反应形成的双苯基网络相一致。2D-BCAs具有金属或准金属特性。其中六种代表性的2D-BCAs展现出良好的晶格动力学和热稳定性、优异的各向异性机械性能以及ORR催化活性。此外，所选的2D-BCAs展现出极高的理论钾存储容量（1116–1489 mAh·g–1）、低迁移势垒（0.03–0.22 eV）和低开路电压（1.10–0.02 V）。这些显著特性使得2D-BCAs有望成为PIB、电催化剂以及电子和离子电子学领域的导体。