MOF-derived multifractal porous carbon with ultrahigh lithium-ion storage performance

Ang Li,Zhihong Li,Gen Chen,Yan Tong,Jisheng Zhou,Xiaohong Chen,Bin Cao,Huaihe Song,Hongmei Luo

doi:10.1038/srep40574

Abstract

Porous carbon is one of the most promising alternatives to traditional graphite materials in lithium-ion batteries. This is not only attributed to its advantages of good safety, stability and electrical conductivity, which are held by all the carbon-based electrodes, but also especially ascribed to its relatively high capacity and excellent cycle stability. Here we report the design and synthesis of a highly porous pure carbon material with multifractal structures. This material is prepared by the vacuum carbonization of a zinc-based metal-organic framework, which demonstrates an ultrahigh lithium storage capacity of 2458 mAh g−1 and a favorable high-rate performance. The associations between the structural features and the lithium storage mechanism are also revealed by small-angle X-ray scattering (SAXS), especially the closed pore effects on lithium-ion storage.

Highlights

A broad pore size distribution have been designed to optimize the conditions for electrolyte permeation and lithium accommodation, which are aroused tremendous interest[13]
A Zn-based Metal-organic frameworks (MOFs) (Zn-MOF) with terephthalic acid as ligand was used as precursor, which exhibits a high Brunauer-Emmet-Teller (BET) specific surface area and a relatively wide pore size distribution
VFPC shows a higher purity of carbon but a lower carbon yield based on MOF precursor (VFPC, 2.19%; FPC, 2.26%), indicating that the vacuum atmosphere can improve the gasification reactions and purify the carbon materials

Summary

Introduction

A broad pore size distribution have been designed to optimize the conditions for electrolyte permeation and lithium accommodation, which are aroused tremendous interest[13] These hierarchical porous carbon materials exhibit an enhanced electrochemical performance than the traditional porous carbon materials[14]. Many works prepared porous carbon from MOFs for the applications in supercapacitors[19,20,21], lithium-sulfur batteries[22,23], oxygen reduction reactions[19,24,25,26], as well as lithium-ion batteries (LIBs)[2,27,28,29,30] Their highly porous structures and heteroatom effects have led to unexpected performances in these fields. The important role of closed pores in lithium storage will be revealed by a comprehensive analysis of porous properties of products using synchrotron radiation small-angle X-ray scattering (SAXS)

Objectives

Methods

Results

Conclusion