Graphdiyne and its heteroatom−doped derivatives for Li−ion/metal batteries

Abstract

Graphdiyne (GDY), which is composed of benzene rings and acetylene linkages units, is a new allotrope of carbon material. Especially, the large triangular pores, with a diameter of 5.4 Å, theoretically predict a higher lithium embedding density compared to traditional graphite anodes, enabling GDY to serve as an effective energy storage material in lithium−ion (Li−ion) battery. GDY is primarily synthesized through the cross−coupling reaction of hexaethynylbenzene (HEB). Under similar preparation conditions, the cross−coupling reaction of other aryne precursors, instead of HEB, results in many GDY heteroatom−doped derivatives. This introduces plenty of heteroatomic defects as well as electrochemically active sites, potentially enhancing electrochemical performance. Recent advancements have been made in utilizing GDY and its heteroatom−doped derivatives as electrode materials or composite materials in Li−ion/metal batteries. This review systematically summarizes the strategies developed for GDY and its heteroatom−doped derivatives. Notably, recent research on the effects of morphology and chemical/electronic structure on performance, particularly new conceptual mechanisms in Li−ion/metal batteries including self−expanding Li−ion transport channels and capture/pores filling−intercalation hybrid mechanism, is briefly described. The results presented here highlight the significant potential of GDY and its heteroatom−doped derivatives for energy storage applications and inspire interest in further development.