Advanced Hierarchical Vesicular Carbon Co-Doped with S, P, N for High-Rate Sodium Storage

Adv Sci (Weinh). 2018 May 8;5(7):1800241. doi: 10.1002/advs.201800241. eCollection 2018 Jul.

Abstract

Hierarchical nanoscale carbons have received wide interest as electrode materials for energy storage and conversion due to their fast mass transfer processes, outstanding electronic conductivity, and high stability. Here, heteroatom (S, P, and N) doped hierarchical vesicular carbon (HHVC) materials with a high surface area up to 867.5 m2 g-1 are successfully prepared using a surface polymerization of hexachloro-cyclotriphosphazene (HCCP) and 4,4'-sulfonyldiphenol (BPS) on the ZIF-8 polyhedrons. Significantly, it is the first time to achieve a controllability of the wall thickness for this unique carbon, ranging from 18 to 52 nm. When utilized as anodes for sodium ion batteries, these novel carbon materials exhibit a high specific capacity of 327.2 mAh g-1 at 100 mA g-1 after 100 cycles, which can be attributed to the expanded interlayer distance and enhanced conductivity derived from the doping of heteroatoms. Importantly, a high capacity of 142.6 mAh g-1 can be obtained even at a high current density of 5 A g-1, assigning to fast ion/electronic transmission processes stemming from the unique hierarchical vesicular structure. This work offers a new route for the fabrication/preparation of multi-heteroatom doped hierarchical vesicular materials.

Keywords: electrochemistry; heteroatom doping; hierarchical vesicular carbon; sodium‐ion batteries.