Energy Storage Mechanism in Supercapacitors with Porous Graphdiynes: Effects of Pore Topology and Electrode Metallicity.

Abstract

Porous graphdiynes are a new class of porous two-dimensional materials with tunable electronic structures and various pore structures. They have potential applications as well-defined nanostructured electrodes and could provide ideal platforms for understanding energy storage mechanisms underlying supercapacitors. Herein, we investigate the effect of stacking structure and metallicity on energy storage with such electrodes. Simulations revealed that supercapacitors based on porous graphdiynes of AB stacking structure could achieve both higher double-layer capacitance and ionic conductivity than AA stacking. This phenomenon is ascribed to more intense image forces in AB stacking, leading to a breakdown of ionic ordering and the formation of effective "free ions". Macroscale analysis shows that doped porous graphdiynes could deliver both outstanding gravimetric and volumetric energy and power densities due to their enhanced quantum capacitance. These findings pave the way for designing high-performance supercapacitors by regulating pore topology and metallicity of electrode materials. This article is protected by copyright. All rights reserved.